Our comprehensive Medical Glossary provides definitions for many of the most common medical terms.

abdomen - area between the chest and the hips that contains the stomach, small intestine, large intestine, liver, gallbladder, pancreas, and spleen.

abdominal bracing - techniSque of tensing the stomach muscles to support the spine.

abdominal hysterectomy - the uterus is removed through the abdomen via a surgical incision.

abdominoscopy - a type of surgery that uses a laparoscope, which is inserted into one or more small incisions, to examine the abdominal cavity. (See also endoscopy, laparoscopy, or minimally invasive surgery.)

ablation - elimination or removal.

ablative therapy - treatment that removes or destroys the function of an organ, as in surgical removal of the ovaries or the administration of some types of chemotherapy that causes the ovaries to stop functioning.

absorption - the way substances pass into tissue as nutrients from food move from the small intestine into the cells of the body.

abutment teeth - the surrounding teeth of each side of the gap where teeth are missing.

accessory digestive organs - organs that help with digestion but are not part of the digestive tract. These organs include the tongue, glands in the mouth that make saliva, pancreas, liver, and gallbladder.  

accessory movement - joint movements that cannot be performed voluntarily or in isolation by the patient.

accommodation - the ability of the eye to focus.  

acetylcholine - a chemical in the brain that acts as a neurotransmitter by sending nerve signals.   

acquired deafness - loss of hearing that occurs or develops over the course of a lifetime; deafness not present at birth.

action tremor - a tremor that increases when the hand is moving voluntarily. 

activated charcoal - an over the counter product that may help relieve intestinal gas.

activities of daily living (ADLs) - personal care activities necessary for everyday living, such as eating, bathing, grooming, dressing, and toileting; a term often used by healthcare professionals to assess the need and/or type of care a person may require.

adenocarcinoma - a cancer that develops in the lining or inner surface of an organ.

adenoma - benign growth starting in the glandular tissue. (See also fibroadenoma.)

adjuvant treatment - treatment that is added to other therapies to increase effectiveness, such as chemotherapy, radiation therapy, or hormone therapy.

adrenal cortex - the outer portion of the adrenal gland that secretes hormones that are vital to the body.

advanced cancer - stage of cancer in which the disease has spread from the primary site to other parts of the body; when the cancer has spread only to the surrounding areas, it is called locally advanced; when it has spread further by traveling through the bloodstream, it

aerophagia - condition that occurs when a person swallows too much air; causes gas and frequent belching.

agonist - a drug capable of combining with receptors to initiate an action that can be known in advance.  

aguesia - loss of the sense of taste.  

akinesia - no movement. 

alactasia - inherited condition involving the lack of the enzyme needed to digest milk sugar.

alimentary canal - digestive tube.

allodynia - a condition in which ordinary, non-painful stimuli evoke pain.

allogeneic bone marrow transplantation - a procedure in which a person receives stem cells from a compatible donor.

alternative medicine - any form of therapy used alone, without recommended standard/conventional treatment.

amenorrhea - absence or cessation of menstrual periods.

American Cancer Society - an organization that supports research, educational materials, and programs, and offers many other services to cancer patients and their families.

American Sign Language (ASL) - manual (hand) language with its own syntax and grammar used primarily by persons who are deaf.

Amsler grid - a chart featuring horizontal and vertical lines used to test vision.

amyloidosis - a rare disease which causes the build-up of amyloid, a protein and starch, in tissues and organs. 

anal fistula - channel that develops between the anus and the skin. Most fistulas are the result of an abscess (infection) that spreads to the skin.

androgen - a hormone that promotes the development and maintenance of male sex characteristics.

anesthesia - loss of feeling or sensation as a result of drugs or gases. General anesthesia causes loss of consciousness; local or regional anesthesia causes loss of feeling only to a specified area.   

anesthetics - drugs that cause loss of sensation to pain or awareness.    

angiotensin-converting enzyme (ACE) inhibitor - a medication that lowers blood pressure.

ankle sprain - overstretched lateral (outside) ligament of the ankle joint.  

anosmia - absence of the sense of smell.

antacids - medicines that balance acids and gas in the stomach.    

anterior chamber of the eye - the front section of the eye's interior where aqueous humor flows in and out of providing nourishment to the eye and surrounding tissues.   

antibiotic - chemical substances, produced by living organisms or synthesized (created) in laboratories, for the purpose of killing other organisms that cause disease.

anticholinergics - medicines that calm muscle spasms in the intestine.    

anticoagulant (Also called blood thinner.) - a medication that keeps blood from clotting.

antidiarrheals - medicines that help control diarrhea.   

antiemetic - drug that prevents or relieves nausea and vomiting (emesis).  

antihistamine drugs - a group of drugs that block the effects of histamine, a chemical released in body fluids during an allergic reaction.

antihypertensive - a medication, or other therapy, that lowers blood pressure.

anti-inflammatory drugs - inflammatory drugsdrugs that reduce the signs and symptoms of inflammation.  

antimetabolites - substances that interfere with the body s chemical processes, such as creating proteins, DNA, and other chemicals needed for cell growth and reproduction; in cancer treatment, antimetabolite drugs disrupt DNA production, which in turn prevents cell divisi

antioxidants - compounds that protect against cell damage inflicted by molecules called oxygen-free radicals, which are a major cause of disease and aging.

antispasmodics - medicines that help reduce or stop muscle spasms.

antrectomy - operation to remove the upper portion of the stomach, called the antrum, often to help reduce the amount of stomach acid.

anus - opening at the end of the digestive tract where bowel contents leave the body.  

aorta - blood vessel that delivers oxygen-rich blood from the left ventricle to the body; it is the largest blood vessel in the body.   

aortic valve - the valve that regulates blood flow from the heart into the aorta.

apex - top portion of the upper lobes of the lungs.

aphasia - total or partial loss of ability to use or understand language; usually caused by stroke, brain disease, or injury.

aphonia - complete loss of voice.

apraxia - inability to make a voluntary movement in spite of being able to demonstrate normal muscle function.   

areola - dark area of skin that surrounds the nipple of the breast.  

arterioles - small branches of arteries.   

artery - a blood vessel that carries oxygenated blood away from the heart to the body.  

arthralgia - pain in a joint, usually due to arthritis or arthropathy.  

arthroplasty - total joint replacement.

articular cartilage - covers the ends of bones and allows the distribution of compressive loads over the cross section of bones; provides frictionless and wear-resistant surface for joint movement.  

articulation disorder - inability to correctly produce speech sounds (phonemes) because of imprecise placement, timing, pressure, speed, or flow of movement of the lips, tongue, and/or throat.

artificial ventilation - the process of supporting breathing by manual or mechanical means when normal breathing is inefficient or has stopped.

ascending colon - part of the colon on the right side of the abdomen.  

assisted reproductive technology (ART) - medical procedures, such as intrauterine insemination, that are performed to help infertile couples conceive.

assistive devices - technical tools and devices such as alphabet boards, text telephones, or text-to-speech conversion software used to assist people with physical or emotional disorders in performing certain actions, tasks, and activities.

atherectomy - a non-surgical procedure that involves removing plaque from the walls of arteries with a rotating blade.

atherosclerosis - a type of arteriosclerosis caused by a build-up of plaque in the inner lining of an artery.  

athetosis - slow, involuntary movements of the hands and feet.  

atonic colon (Also called lazy colon.) - lack of normal muscle tone or strength in the colon.

atresia - lack of a normal opening from the esophagus, intestines, or anus. 

atrioventricular (AV) node - a cluster of cells between the atria and ventricles that regulate the electrical current.

atrioventricular block - an interruption of the electrical signal between the atria and the ventricles.

atrium (pl. atrial) - one of two upper chambers in the heart.

atrophic gastritis - chronic inflammation of the stomach that causes the breakdown of the mucous membranes of the stomach.

atrophy - a continuous decline of a body part or tissue, usually a muscle, following a period of disuse or immobility.

atypical - not usual; abnormal; often refers to the appearance of pre-cancerous or cancerous cells. (See also hyperplasia.)

auditory brainstem response (ABR) test - test used to screen for hearing impairments in infants and young children.

auditory nerve - eighth cranial nerve that connects the inner ear to the brainstem.

auditory perception - ability to identify, interpret, and attach meaning to sound.

auditory prosthesis - device that substitutes or enhances the ability to hear.

augmentative devices - tools that help individuals with limited or absent speech to communicate. 

aural rehabilitation - techniques used with people who are hearing impaired to improve their ability to speak and to communicate.

autoimmune process - a process where the body's immune system attacks and destroys body tissue that it mistakes for foreign matter.

autologous transplant - a procedure in which a patient's own bone marrow is removed, treated with anticancer drugs or radiation, then returned to the patient. 

autopsy - examination of a body after death; performed to determine cause of death, or to verify a diagnosis.

avascular necrosis - death of tissue due to a depletion of blood supply.

avulsion - when a muscle is forcefully stretched beyond its freely available range of motion, or when it meets a sudden, unexpected resistance while contracting forcefully.     

axilla - armpit.   

axillary dissection - a surgical procedure in which the lymph nodes in the armpit (axillary nodes) are removed and examined; often used to determine if breast cancer has spread to the axillary nodes.  

axon - the long, hair like extension of a nerve cell that carries a message to a nearby nerve cell.  

balance - biological system that enables individuals to know where their bodies are in the environment and to maintain a desired position; normal balance depends on information from the labyrinth in the inner ear, and from other senses such as sight and touch.

balance disorder - disruption in the labyrinth - the inner ear organ that controls the balance system allowing individuals to know where their bodies are in the environment.

balloon angioplasty (Also called coronary artery balloon dilation.) - a procedure used to widen narrowed arteries. The procedure uses a catheter with a deflated balloon at the tip that is inserted into the narrowed part of the artery. The balloon is then inflated, causing the artery to dilate (widen).

barium - a metallic, chemical, chalky, liquid used to coat the inside of organs so that they will show up on an x-ray.

barium swallow - upper gastrointestinal (GI) series.

barotrauma - injury to the middle ear caused by a reduction of air pressure.

basal body temperature - temperature of a person's body taken first thing in the morning after several hours of sleep and before any activity, including getting out of bed or talking; often charted to determine the time of ovulation.

basal ganglia - several large clusters of nerve cells, including the striatum and the substantia nigra, deep in the brain below the cerebral hemispheres.

basal metabolic rate (BMR) - a measurement of energy required to keep the body functioning at rest. Measured in calories, metabolic rates increase with exertion, stress, fear, and/or illness.

base of the lung - bottom portion of lower lobes of the lungs, located just above the diaphragm. 

beta blocker - an antihypertensive medication that limits the activity of epinephrine (a hormone that increases blood pressure).

beta cells - cells that make insulin, found in areas of the pancreas called the islets of Langerhans.

biarthrodial muscles - muscles that span over two joints and have a function over those joints.

bilateral - affecting both sides of the body; for example, bilateral breast cancer is cancer occurring in both breasts at the same time (synchronous) or at different times (metachronous).

biliary tract (Also called biliary system or biliary tree.) - gallbladder and the bile ducts.   

binocular vision - the ability to use both eyes at once.

bladder - a hollow organ that urine drains into from the kidneys.

blink rate - the number of times per minute that the eyelid automatically closes - normally 10 to 30 times per minute. 

blood plasma - the fluid part of blood that contains nutrients, glucose, proteins, minerals, enzymes, and other substances.

blood pressure cuff - a device usually placed around the upper part of the arm to measure blood pressure.

blood-brain barrier - the protective membrane that separates circulating blood from brain cells.  

body mass index (BMI) - a number, derived by using height and weight measurements, that gives a general indication of whether or not weight falls within a healthy range.

bone - living tissue that makes up the body's skeleton. 

bone density test - a test that measures the strength and density of bones; often used to determine the risk of developing osteoporosis.

borborygmi (Also called stomach "growling".) - rumbling sounds caused by gas moving through the intestines.

botanical - of plants and plant life.

bowel - another word for the small and large intestines.

bowel movement - body wastes passed through the rectum and anus.

bowel prep - process used to clean the colon with enemas and a special drink; used before surgery of the colon, colonoscopy, or barium x-ray and other imaging exams. (See also lavage.)

bradycardia - abnormally slow heartbeat.  

bradykinesia - slowness of movement.

bradyphrenia - slowness of thought processes.

brain attack - another name for stroke.

brain scan - an imaging method used to find abnormalities in the brain, including brain cancer and cancer that has spread to the brain from other places in the body.

brainstem implant - auditory prosthesis that bypasses the cochlea and auditory nerve to help individuals who cannot benefit from a cochlear implant because the auditory nerves are not working.

Braxton Hicks contractions - relatively brief, painless contractions of the uterus that may begin during the second half of pregnancy. 

BRCA1 - a gene, which, when damaged or mutated, places a woman at much higher risk of developing breast and/or ovarian cancer than the general population.

BRCA2 - a gene, which, when damaged or mutated, places a woman at a much higher risk for developing breast cancer and/or ovarian cancer than the general population.

breast cancer - a cancerous tumor of the breast tissue.

breast conservation therapy - surgery to remove a breast cancer and a small amount of benign tissue around the cancer without removing any other part of the breast. This procedure is also called lumpectomy, segmental excision, limited breast surgery, or tylectomy.

breast implant - a manufactured sac that is filled with silicone gel (a synthetic material) or saline (sterile saltwater); the sac is surgically inserted to increase breast size or restore the contour of a breast after mastectomy.

breast reconstruction - surgery to rebuild a breast mound after mastectomy.

breast specialist - term describing health care professionals who have a dedicated interest in breast health. While they may acquire specialized knowledge in this area, medical licensing boards do not certify a specialty in breast care.

bronchodilators - a group of drugs that widen the airways in the lungs.

bronchus (pl. bronchi) - one of the two large airways of the lungs. The trachea divides into the right and left bronchi.

Budd-Chiari syndrome - a rare liver disease in which the veins that drain blood from the liver are blocked or narrowed.

bulking agents - laxatives that make bowel movements soft and easy to pass.

bundle-branch block - a condition in which the heart's electrical system is unable to normally conduct the electrical signal.

calculi - stones or solid lumps such as gallstones.

calluses - thick, hardened areas of the skin, usually on the foot, caused by friction or pressure.

cancellous tissue - the sponge-like tissue inside bones.

cancer - abnormal cells that divide without control, which can invade nearby tissues or spread through the bloodstream and lymphatic system to other parts of the body.

capillaries - tiny blood vessels between arteries and veins that distribute oxygen-rich blood to the body.

capsule - the layer of cells around an organ, such as the capsule of the prostate.

carcinogen - a substance that is known to cause cancer.

cardiac - pertaining to the heart.

cardiac arrest - the stopping of heartbeat.  

cardiac output - total amount of blood being pumped by the heart over a particular period of time.  

cardiology - the clinical study and practice of treating the heart.  

cardioversion - the procedure of applying electrical shock to the chest to change an abnormal heartbeat into a normal one.   

Caroli's disease - An inherited condition in which bile ducts in the liver are enlarged and may cause irritation, infection, or gallstones.

carotid arteries - the major arteries in the neck that supply blood to the brain.

cartilage - a smooth material that covers bone ends of a joint to cushion the bone and allow the joint to move easily without pain.

cathartics - laxatives.

catheter - a flexible tube used to drain fluid from or inject fluid into the body. The most common catheter is the Foley catheter, used to drain urine from the bladder.

cecostomy - tube that goes through the skin into the beginning of the large intestine to remove gas or feces; it is a short-term way to protect part of the colon while it heals after surgery.

cecum - beginning of the large intestine; it is connected to the lower part of the small intestine, called the ileum.

central auditory processing disorder - inability of individuals with normal hearing and intelligence to differentiate, recognize, or understand sounds.

cerebellum - a large structure consisting of two halves (hemispheres) located in the lower part of the brain; responsible for the coordination of movement and balance.

cerebral embolism - a blood clot from one part of the body that is carried by the bloodstream to the brain where it blocks an artery.

cerebral hemorrhage - bleeding within the brain.  

cerebral thrombosis - formation of a blood clot in an artery that supplies blood to the brain.

cerebrovascular - pertaining to blood vessels in the brain.

cerebrovascular accident (Also called stroke.) - an impeded blood supply to the brain.   

cerebrovascular occlusion - an obstruction in the blood vessel in the brain.

cerebrum - consists of two parts (lobes), left and right, which form the largest and most developed part of the brain; initiation and coordination of all voluntary movement take place within the cerebrum. The basal ganglia are located immediately below the cerebrum.

cesarean delivery (Also called cesarean section or C-section.) - surgical procedure to deliver a baby through an incision in the lower abdomen and uterus.

chemosensory disorders - disorders or diseases of smell and/or taste.

chlorhydria - too much hydrochloric acid in the stomach.

cholangiography - series of x-rays of the bile ducts.   

cholecystitis - inflammation of the gallbladder wall.  

cholelithiasis - a condition in which gallstones are present in the gallbladder.

chorea - rapid, jerky, dance-like movement of the body.

chyme - thick liquid made of partially digested food and stomach juices; made in the stomach and moves into the small intestine for further digestion. 

cineangiography - a procedure that involves taking moving pictures to show the passage of dye through blood vessels.

circulatory system - pertaining to the heart and blood vessels, and the circulation of blood. 

claudication - pain or fatigue in arms and legs due to a poor supply of oxygen to the muscles.    

clinical trials - studies, involving patients, aimed at finding better ways to prevent, detect, diagnose, or treat cancer.

coccydynia - pain around the coccyx.  

cochlea - snail-shaped structure in the inner ear that contains the organ of hearing.

cochlear implant - medical device that bypasses damaged structures in the inner ear and directly stimulates auditory nerves to allow some deaf individuals to learn to hear and interpret sounds and speech.

colectomy - partial or complete removal of the large bowel or colon.

colon - large intestine. 

colon polyps - small, fleshy, mushroom-shaped growths in the colon.  

colonic inertia - condition of the colon when muscles do not work properly, causing constipation.

colonoscopic polypectomy - removal of tumor-like growths (polyps) using a device inserted through a colonoscope.

colony-stimulating factors - substances that stimulate the production of blood cells.

colorectal cancer - cancer that occurs in the colon (large intestine) or the rectum (the end of the large intestine).

colorectal transit study - test to see how food moves through the colon.

colostrum - thin, white, first milk produced by the breasts during late pregnancy and for a few days after childbirth. It provides a nursing infant with essential nutrients and infection-fighting antibodies.  

common bile duct - tube that carries bile from the liver to the small intestine.

compact tissue - the harder, outer tissue of bones.

comparative pathology - the study of disease in animals and how it compares in humans.

complementary medicine - any form of therapy used in combination with other alternative treatments or standard/conventional medicine.

computed tomography (CT or CAT scan) - a non-invasive procedure that takes cross-sectional images of the brain or other internal organs; to detect any abnormalities that may not show up on an ordinary x-ray.

conductive hearing impairment - hearing loss caused by dysfunction of the outer or middle ear.

continence - ability to hold in a bowel movement or urine.

contusion - a bruise caused by a blow to the muscle, tendon, or ligament; caused when blood pools around the point of injury and discolors the skin.

cornea - the clear, dome-shaped surface that covers the front of the eye.  

corneal curvature - the shape of the front surface of the eye.

coronary artery bypass graft (CAB or CABG) - a surgical procedure in which a healthy blood vessel is transplanted from another part of the body into the heart to replace or bypass a diseased vessel.

coronary heart disease - a condition in which the coronary arteries narrow from an accumulation of plaque (atherosclerosis) and cause a decrease in blood flow.

coronary occlusion - an obstruction of one of the coronary arteries that decreases flow to the heart muscle.

coronary thrombosis - the formation of a clot in one of the arteries that carry blood to the heart muscle.

cortex - the outer layer of the cerebrum, densely packed with nerve cells.   

corticosteroids - potent anti-inflammatory hormones that are made naturally in the body or synthetically for use as drugs. The most commonly prescribed drug of this type is prednisone.

craniectomy - excision of a part of the skull.

craniotomy - surgical opening of the skull to gain access to the intracranial structures.

crepitus - grinding noise or sensation within a joint.

cupping - the use of warmed glass jars to create suction on certain points of the body.

cyanosis - bluish color in the skin due to insufficient oxygen levels in the blood. 

cyclic vomiting syndrome (CVS) - sudden, repeated attacks of severe vomiting (especially in children), nausea, and physical exhaustion with no apparent cause.

cystic duct - tube that carries bile from the gallbladder into the common bile duct and the small intestine.

cystometry - diagnostic procedure that measures bladder capacity and pressure changes as the bladder fills and empties.

cytology - the study of individual cells.

debridement - the surgical removal of foreign material and/or dead, damaged, or infected tissue from a wound or burn.

decibel - unit that measures the intensity or loudness of sound.

deciduous teeth - also known as "baby" or primary teeth.

defecation - passage of bowel contents through the rectum and anus.

defecography - x-ray of the anus and rectum to see how the muscles work to move stool.  

defibrillator - an electronic device used to establish normal heartbeat.

delayed gastric emptying - gastroparesis.

delusions - a condition in which the patient has lost touch with reality and experiences hallucinations and misperceptions.

dendrite - a thread-like extension from a nerve cell that serves as an antenna to receive messages from the axons of other nerve cells.  

dental implants - small dental appliances that are inserted into the upper and lower jaws to help restore a mouth that has little or no non-restorable teeth. 

dental pulp - the soft tissue around the tooth that contains nerves, blood vessels, and connective tissue.

dental sealant - a thin, plastic film that is painted on the chewing surfaces of the back teeth - the molars and premolars - to prevent tooth decay.

depth perception - the ability to distinguish objects in a visual field.

dermatopathology - the study of the skin in diagnosing skin diseases.

descending colon - the middle part of the colon located on the left side of the abdomen.

diagnosis - identifying a disease by its signs, symptoms, and laboratory findings.

diaphragm - primary muscle used for respiration, located just below the lung bases.

diastolic blood pressure - the lowest blood pressure measure in the arteries, which occurs between heartbeats.

diathermy machine - a piece of equipment used in the operating room to control bleeding.

digestants - medicines that aid or stimulate digestion.

digestion - process the body uses to break down food into simple substances for energy, growth, and cell repair.

digestive system - the group of organs that break down foods into chemical components that the body can absorb and use for energy, and for building and repairing cells and tissues. 

digital rectal exam (DRE) - procedure in which the physician inserts a gloved finger into the rectum to examine the rectum and the prostate gland for signs of cancer.

dilate - relax; expand.

dilation and curettage (D & C) - a common gynecological surgery which consists of widening the cervical canal with a dilator and scraping the uterine cavity with a curette.

diplopia - double vision.

disc herniation (Also called disc prolapse, disc bulge, or slipped disc.) - disruption to the normal integrity of the intervertebral disc.  

distention - bloating or swelling of the abdomen. 

diuretic - a medication that lowers blood pressure.

diverticulosis - condition that occurs when small pouches (diverticula) push outward through weak spots in the colon.

diverticulum - small pouch in the colon. These pouches are not painful or harmful unless they become infected or irritated.  

dopamine - a chemical substance, a neurotransmitter, found in the brain that regulates movement, balance, and walking. 

dumping syndrome (Also called rapid gastric emptying.) - condition that occurs when food moves too fast from the stomach into the small intestine.

dysarthia - group of speech disorders caused by disturbances in the strength or coordination of the muscles of the speech mechanism as a result of damage to the brain or nerves.

dysentery - infectious disease of the colon. Symptoms include bloody, mucus-filled diarrhea, abdominal pain, fever, and loss of fluids from the body.

dysequilibrium - any disturbance of balance.

dysfluency - disruption in the smooth flow or expression of speech.

dysgeusia - distortion or absence of the sense of taste.

dyskinesia - an involuntary movement including athetosis and chorea.

dysosmia - distortion or absence of the sense of smell.

dyspareunia - pain in the vagina or pelvis experienced during sexual intercourse.

dyspepsia - indigestion.

dysphagia - difficulty in swallowing.  

dysphonia - any impairment of the voice or difficulty speaking.  

dysplasia - an abnormality of growth.

dyspnea - shortness of breath.  

dyspraxia of speech - partial loss of the ability to consistently pronounce words in individuals with normal muscle tone and coordination of the speech muscles.

dysrhythmia - an abnormal heart rhythm.

dystonia - a slow movement or extended spasm in a group of muscles.

dystrophin - a protein found in normal muscle tissue.

ear infection - presence and growth of bacteria or viruses in the ear.

ear wax - yellow secretion from glands in the outer ear (cerumen) that keeps the skin of the ear dry and protected from infection.

eczema - inflammation of the skin that causes itching and, sometimes, crusting, scaling, or blisters.

edema - swelling due to the build-up of fluid. 

elective surgery - an operation the patient chooses to have done, which is not required.

electrocardiogram (ECG or EKG) - a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle damage.

electrocoagulation - procedure that uses a high frequency current to harden tissue.  

electrodesiccation - electrosurgery which destroys tissue.

electromyogram (EMG) - a test to evaluate nerve and muscle function.

electrophysiological study (EPS) - a cardiac catheterization to study electrical current in patients who have arrhythmias.

electrosurgery - use of high-frequency electrical currents to destroy cancer cells.

emergency surgery - an operation performed immediately as a result of a urgent medical condition.

encephalitis - a viral infection of the brain.

endarterectomy - the surgical removal of plaque or blood clots in an artery.

endocardium - the membrane that covers the inside surface of the heart.

endodontist (Also called a pulp specialist.) - an endodontist has undergone specialized training in performing root canal therapy.

endolymph - fluid in the labyrinth - the organ of balance located in the inner ear.

endometrium - mucous membrane lining of the inner surface of the uterus that grows during each menstrual cycle and is shed in menstrual blood.  

endorphins - endogenous biomechanical substances implicated in the alleviation of pain, produced as a result of body stress.

endoscopic sphincterotomy (Also called endoscopic papillotomy.) - operation to cut the muscle between the common bile duct and the pancreatic duct.

endothelium - the layer of cells that lines the heart, blood vessels, and other body cavities.

enema - liquid put into the rectum to clear out the bowel or to administer medications or food.

enteral nutrition (Also called tube feeding.) - way to provide food through a tube placed in the nose, the stomach, or the small intestine. A tube in the nose is called a nasogastric or nasoenteral tube. A tube that goes through the skin into the stomach is called a gastrostomy or percutaneous endoscop 

enteroscopy - examination of the small intestine with an endoscope.

enterostomy - ostomy, or opening, into the intestine through the abdominal wall.

eosinophilic gastroenteritis - infection and swelling of the lining of the stomach, small intestine, or large intestine.

epicardium - the membrane that covers the outside of the heart.

epidural anesthetic - an anesthetic which is injected into the "epidural space" in the middle and lower back, just outside the spinal space, to numb the lower extremities.

epinephrine - one of two chemicals (the other is norepinephrine) released by the adrenal gland that increases heart rate and force of the heart contraction, and narrows blood vessels.

ergonomics - the study of how the workplace relates to human functions.

eructation - belching.

esophageal ulcer - sore in the esophagus caused by long-term inflammation or damage from the residue of pills.

esophageal varices - stretched veins in the esophagus that occur when the liver is not working properly.

estrogen - a hormone secreted by the ovaries which affect many aspects of the female body, including menstrual cycles and pregnancy.

estrogen replacement therapy (ERT) - use of the female hormone estrogen to replace that which the body no longer produces naturally after medical or surgical menopause.

euphoria - a feeling of well-being or elation; may be drug related.    

excisional - cutting away cancerous tissue with a scalpel, or other instruments, to completely remove it and possibly some surrounding tissue. There are many types of excisional surgeries, each named for the particular area of the body in which they are performed, or

excrete - to get rid of waste from the body. 

expiration - exhaling; giving off carbon dioxide. 

extensor muscle - any muscle that causes the straightening of a limb or other part.

external urethral sphincter muscle - a voluntary and involuntary ring-like band of muscle fibers that voluntarily contract to stop urinating.

extrapyramidal system - system consisting of nerve cells, nerve tracts, and pathways that connects the cerebral cortex, basal ganglia, thalamus, cerebellum, reticular formation, and spinal neurons that is concerned with the regulation of reflex movements such as balance and walk

extrinsic asthma - asthma that is triggered by an allergic reaction - usually to something that is inhaled.

fallopian tubes - two thin tubes that extend from each side of the uterus, toward the ovaries, as a passageway for eggs and sperm.

fatty liver (Also called steatosis.) - build-up of fat in liver cells.

fecal incontinence - being unable to hold stool in the colon and rectum.

fecal occult blood test - test to check for hidden blood in stool; screening test for cancer of the colon or rectum.   

femur - thighbone.

festination - walking with a series of quick, small, shuffling steps as if hurrying forward to keep balance.

fibrillation - rapid contractions of the heart muscle.

fibroadenoma - noncancerous, firm, rubbery lump in the breast that is painless and moves around easily when touched.

fibrocystic breasts - noncancerous condition in which small lumps and cysts develop in the breasts.

fibroids - noncancerous growths in, on, or within the walls of the uterus.

fibrosis - the growth of scar tissue possibly due to infection, inflammation, injury, or even healing.

fibrositis - a benign, intermittently recurring, and protracted disease process, with a lack of underlying pathology.

fine needle aspiration - the use of a thin, hollow needle to withdraw tissue from the body.

flexor muscle - any muscle that causes the bending of a limb or other body part.

flutter - ineffective contractions of the heart muscles.

follicle-stimulating hormone (FSH) - hormone secreted by the pituitary gland in the brain that stimulates the growth and maturation of eggs in females and sperm in males, and sex hormone production in both males and females.

food exchanges - a way to help people stay on special food plans by letting them replace items from one food group with items from another group.

food intolerance - an adverse food-induced reaction that does not involve the immune system (i.e., lactose intolerance).

free skin graft - the detaching of healthy skin from one part of the body to repair areas of lost or damaged skin in another part of the body.

frozen shoulder - alternate name for "capsulitis" of the shoulder, which undergoes four distinct stages: pain; pain and stiffness; stiffness; resolution.

functional disorders (Also called motility disorders.) - conditions that result from poor nerve and muscle function.

functional incontinence - difficulty reaching a restroom in time because of physical conditions such as arthritis.

gait - pattern of locomotion.    

ganglion - a cluster of nerve cells.    

ganglion cysts - non-cancerous, fluid-filled cysts are common masses or lumps in the hand and usually found on the back of the wrist.

Gardner's syndrome - condition in which many polyps form throughout the digestive tract.

gas - air that comes from the normal breakdown of food and is passed out of the body through the rectum (flatus) or the mouth (belch).

gastric - related to the stomach.

gastric juices - liquids produced in the stomach to help break down food and kill bacteria.

gastrocolic reflex - increase of muscle movement in the gastrointestinal tract when food enters an empty stomach; may cause the urge to have a bowel movement right after eating.

gastroenteritis - infection or irritation of the stomach and intestines, which may be caused by bacteria or parasites from spoiled food or unclean water, or eating food that irritates the stomach lining and emotional upsets such as anger, fear, or stress.

gastroenterologist - physician who specializes in digestive diseases.

gastroenterology - field of medicine concerned with the function and disorders of the digestive system.

gastrointestinal (GI) tract (Also called the alimentary canal or digestive tract.) - a large, muscular tube that extends from the mouth to the anus, where the movement of muscles and release of hormones and enzymes digest food.  

gastrostomy - an artificial opening from the stomach to a hole (stoma) in the abdomen where a feeding tube is inserted. (See also enteral nutrition.)

general anesthetic - an anesthetic which causes the patient to become unconscious during surgery.

genes - basic, functional units of heredity, each occupying a specific place on a chromosome.

genital herpes - a sexually transmitted disease caused by the herpes simplex virus.  

glucose - a simple sugar, which is the body's main source of energy.   

gluten sensitive enteropathy (Also called celiac sprue or celiac disease.) - a sensitivity to gluten - a wheat protein. Individuals with this disease must avoid gluten-containing grains, which include all forms of wheat, oats, barley, and rye.

gluteus maximus - the large, superficial buttock muscle.

glycogen - converted glucose for storage. Glycogen plays a role in controlling blood sugar levels.

gonads - ovaries and testes.

grades of movement - standardized means of documenting techniques of mobilization, relating it to the true feel of joint movement.

grading - a process for classifying cancer cells to determine the growth rate of the tumor. The cancer cells are measured by how closely they look like normal cells.   

granuloma - mass of red, irritated tissue in the gastrointestinal tract found in Crohn's disease. 

gray matter - the darker-colored tissues of the central nervous system; in the brain, the gray matter includes the cerebral cortex, the thalamus, the basal ganglia, and the outer layers of the cerebellum.

gustation - act or sensation of tasting.

hair cells - sensory cells of the inner ear, which are topped with hair-like structures (stereocilia), which transform the mechanical energy of sound waves into nerve impulses.

halitosis - an oral health condition characterized by consistently odorous breath.

hallux rigidus - loss of range of the movement of the metatarsophalangeal (MTP) joint of the first (great) toe.  

hamstrings - muscles located in the posterior compartment of the thigh.  

hay fever - see rhinitis.

headache, primary - includes tension (muscular contraction), vascular (migraine), and cluster headaches not caused by other underlying medical conditions.

headache, secondary (Also called traction headaches or inflammatory headaches.) - includes headaches that result from other medical conditions.

hearing - series of events in which sound waves in the air are converted to electrical signals that are sent as nerve impulses to the brain where they are interpreted.

hearing aid - electronic device that brings amplified sound to the ear.

hearing disorder - disruption in the normal hearing process; sound waves are not converted to electrical signals and nerve impulses are not transmitted to the brain to be interpreted.  

heart block - interrupted electrical impulse to heart muscles.    

heart valve prolapse - a condition of the heart valve in which it is partially open when it should be closed.    

heartbeat - one complete contraction of the heart.

heart-lung machine - a machine that performs for the heart during open heart surgery.

Heberden's nodes - bony swellings around the margins of joints, associated with degenerative changes of arthritis.

hematopathology - the study of blood, bone marrow and the organs and tissues that use blood cells to perform their functions.

hemorrhage - the medical term for bleeding. 

hemorrhoidectomy - the surgical removal of hemorrhoids. 

hepatitis E - virus spread mostly through unclean water. This type of hepatitis is common in developing countries and has not occurred in the United States.

hepatology - field of medicine concerned with the functions and disorders of the liver.

high density lipoprotein (HDL) - the "good" cholesterol that promotes breakdown and removal of cholesterol from the body.

hip - the region on each side of the pelvis that is made up of three sections: ilium, ischium, and pubis; the upper part of the femur (upper leg bone) fits into the hip via a ball-and-socket joint; the socket is a cup-shaped bone of the pelvis called the acetab

histamine - a chemical present in cells throughout the body that is released during an allergic reaction.

hives - see urticaria

hormone replacement therapy (HRT) - use of the female hormones estrogen and progestin (a synthetic form of progesterone) to replace those the body no longer produces after menopause.

hormone therapy - the use of hormones, medications, or surgery to suppress (block) or mimic hormones and alter the growth of hormone-sensitive cancer.

hormones - chemical substances created by the body that control numerous body functions.

human papillomaviruses (HPVs) - a group of viruses that can cause warts. Some HPVs are sexually transmitted and cause wart-like growths on the genitals. HPV is a major risk factor for cervical cancer.  

hyaloid canal - narrow passageway that allows blood to flow through the eye.

hydrocortisone - a hormone secreted by the adrenal cortex which affects metabolism.  

hydrogen breath test - test for lactose intolerance that measures breath samples for too much hydrogen.

hydrotherapy - use of water as a medical treatment

hyperextension - active or passive force which takes the joint into extension, but beyond its normal physiological range.

hyperglycemia - high levels of glucose in the blood. 

hyperopia - farsightedness

hyperplasia, endometrial - excessive growth of cells in the endometrium.

hypertrophy - an increase in the size of tissue

hypogeusia - diminished sensitivity to taste 

hypomobility - a decrease in the normal range of joint movement.

hyposmia - diminished sensitivity to smell   

hypotension - abnormally low blood pressure

hypothalamus - small structure at the base of the brain that regulates many body functions, including appetite and body temperature.

hypoxia - depletion of oxygen in the cells and tissues

hysteroscope - visual examination of the canal of the cervix and the interior of the uterus using a viewing instrument (hysteroscope) inserted through the vagina.

ice therapy - cooling of deeper tissues

idiopathic - of unknown origin  

ileocolitis - irritation of the lower part of the small intestine (ileum) and colon

ileostomy - operation that makes it possible for stool to leave the body, after the colon and rectum are removed, in which an opening is made in the abdomen and the bottom of the small intestine (ileum) attaches to it. 

ileum - lower end of the small intestine.

imaging - tests or evaluation procedures that produce pictures of areas inside the body.

immobilization - preventing movement to allow for natural healing to take place.

immune system - complex network of specialized cells and organs that work together to defend the body against attacks by "foreign" invaders such as bacteria and viruses.

immunoglobulin E (IgE) - a type of antibody, formed to protect the body from infection, which attaches to mast cells in the respiratory and intestinal tracts and may cause allergic rhinitis, asthma, or eczema.    

immunoglobulins - antibodies or proteins found in blood and tissue fluids produced by cells of the immune system to bind to substances in the body that are recognized as foreign antigens. Immunoglobulins sometimes bind to antigens that are not necessarily a threat to healt

immunology - the study of the body's immune system - its functions and disorders.

immunosuppresive medications - medications that suppress the body's immune system; often used to minimize rejection of transplanted organs.   

immunotherapy (Also called biological therapy.) - treatment that uses the body's natural defenses to fight disease.

impaction - trapping of an object in a body passage, such as stones in the bile duct or hardened stool in the colon.

impaired glucose tolerance (IGT) - a condition in which blood sugar levels are higher than normal, but are not high enough to be classified as diabetes; a risk factor for type 2 diabetes.

impedance plethysmography - a test to evaluate blood flow through the leg.

in vitro fertilization - treatment for infertility in which a woman's egg is fertilized, outside her body, with her partner's sperm or sperm from a donor.

infection - the invasion of the body by microorganisms that cause disease.

inferior vena cava - the large blood vessel (vein) that returns blood from the legs and abdomen to the heart.

inflammation - characteristic reaction of tissues to injury or disease marked by four signs: swelling, redness, heat, and pain.  

inflammatory bowel disease (IBD) - long-lasting problems that cause irritation and ulcers in the gastrointestinal (GI) tract - the most common disorders are ulcerative colitis and Crohn's disease.

informed consent form - a form signed by the patient prior to surgery which explains everything involved in the surgery, including its risks.

inner ear - part of the ear that contains both the organ of hearing (the cochlea) and the organ of balance (the labyrinth). 

inotropic medications - medications that increase strength of the contractions in the heart.

inpatient surgery - surgery which requires the patient to be admitted and stay in the hospital.

inspiration - inhaling; taking in oxyge

insulin - a hormone produced by the pancreas. Insulin affects the amount of glucose absorbed by the liver.   

intercostal muscles - muscles lying between ribs; often injured by rotary stress of the thorax.

interferon - a biological response modifier that stimulates the growth of certain disease-fighting blood cells in the immune system; used to treat cancer and other diseases.

interleukin-2 - a biological response modifier that stimulates the growth of certain blood cells in the immune system that can fight cancer and other diseases.

intervertebral disc - disc that forms a cartilaginous joint between the vertebral bodies, to provide shock absorption.

intestinal mucosa - surface lining of the intestines where the cells absorb nutrients.  

intestines - see large intestine and small intestine.  

intolerance - allergy or sensitivity to a food, drug, or other substance.

intra-articular - within the joint 

intrauterine insemination - treatment for infertility in which semen is introduced into the uterus via a slim tube inserted through the vagina.

intravenous line - a thin plastic tube inserted into a vein (usually in the patient s forearm) through which a volume of fluid is injected into the bloodstream.

intrinsic asthma - asthma that has no apparent external cause.    

invasive cancer - cancer that begins an one area and then spreads deeper into the tissues of that area.

ischemia - decreased flow of oxygenated blood to an organ due to obstruction in an artery.

ischemic heart disease - coronary artery disease or coronary heart disease caused by narrowing of the coronary arteries and decreased blood flow to the heart.

isometric - muscle contraction without movement at the joint.  

isthmus - tissue that connects the two lobes of the thyroid.

jaundice - a yellow discoloration of the skin and whites of the eyes due to abnormally high levels of bilirubin (bile pigmentation) in the bloodstream.

jejunum - middle section of the small intestine between the duodenum and ileum.

joint - where the ends of two or more bones meet.

joint locking - extremely painful condition usually caused by entrapment of a loose body within the joint, between the joint surfaces.

Jordan frame - specialized stretcher developed for transport of patients with a suspected spinal injury.   

jugular veins - veins that carry blood from the head back to the heart.

Jumper's knee - associated with a small area of degeneration of the tendon attachment at the lower pole of the patella (knee-cap), characterized by pain and extreme local tenderness. 

juvenile rheumatoid arthritis (JRA) - a form of arthritis in children ages 16 or younger that causes inflammation and stiffness of joints for more than six weeks. Unlike adult rheumatoid arthritis, which is chronic and lasts a lifetime, children often outgrow juvenile rheumatoid arthritis. However, the disease can affect bone development in the growing child.

keloids - smooth, pink, raised, firm, fibrous growths on the skin that form secondary to injury.

keratitis - inflammation of the cornea.

keratoacanthomas - round, flesh-colored growths with craters that contain a pasty material.

keratosis pilaris - a common skin condition characterized by small, pointed bumps, especially on the back and sides of the upper arms.

ketoacidosis - high blood glucose, often caused by illness or taking too little insulin.   

ketone - break down product of fat that accumulates in the blood as a result of inadequate insulin or inadequate calorie intake.

kidney stone - a solid piece of material that forms from crystallization of excreted substances in the urine.

kidneys - a pair of bean-shaped organs located below the ribs toward the middle of the back.

knee reconstruction - surgical restoration of biomechanics of the knee.

kyphosis - a forward curvature of the back bones (vertebrae) in the upper back area, giving a "humpback" appearance.

labyrinth - organ of balance located in the inner ear; consists of three semicircular canals and the vestibule.

lactase - enzyme in the small intestine needed to digest milk sugar (lactose).

lactase deficiency - lack of the lactase enzyme.   

lactose - sugar found in milk, which the body breaks down into galactose and glucose.

laminectomy - surgical procedure which includes removal of a portion of the lamina, to provide more room in the vertebral canal; usually performed to treat disc herniation or spinal canal stenosis.

language - system for communicating ideas and feelings using sounds, gestures, signs, or marks.  

laparoscope - thin tube with a tiny video camera attached, used to look inside the body and see the surface of organs. (See also endoscope.)

laparoscopic cholecystectomy - an operation to remove the gallbladder. The doctor inserts a laparoscope, and other surgical instruments, through small holes in the abdomen. The camera allows the doctor to see the gallbladder on a television screen. The doctor removes the gallbladder th

laparoscopic lymph node sampling - lymph nodes are removed through a viewing tube called a laparoscope, which is inserted through a small incision in the abdomen.

laparoscopic lymphadenectomy - the removal of pelvic lymph nodes with a laparoscope through small incisions in the lower abdominal region.

laparotomy - a surgical procedure that involves an incision into the abdominal cavity; often used when making a diagnosis when less invasive tests are difficult or not possible. 

large intestine - part of the intestine that goes from the cecum to the rectum.    

laryngeal nodules - noncancerous, callous-like growths on the inner parts of the vocal folds (vocal cords).

laryngeal paralysis - loss of function or feeling of one or both of the vocal folds.

laryngectomy - surgery to remove part or all of the larynx or voice box.   

larynx - valve structure between the trachea (windpipe) and the pharynx (the upper throat); the primary organ of voice production.

lavage - the process of washing (cleaning) of an organ such as the bowel or stomach.

laxatives (Also called cathartics.) - medications to relieve long-term constipation.

lens (Also called crystalline lens.) - the transparent structure inside the eye that focuses light rays onto the retina.

lesion - an injury or wound.

levodopa (L-dopa) - an effective anti-Parkinson drug, that is changed into dopamine in the brain.

ligament - a flexible band of fibrous tissue that connects the bones and bind the joints together.

lipid - a fatty substance in the blood.

lipoproteins - transporters of fatty substances in the blood.

liver - largest organ in the body; performs important functions such as making bile, changing food into energy, and cleaning alcohol and poisons from the blood.

lobectomy - removal of a lobe of the lung, for cancer, benign tumors, or infections.

lobule - a subdivision of a lobe or a small lobe.

local anesthesia - anesthetic medicine injected into the site of the operation to temporarily numb that area.

loose body - name given to an object, located within a joint, that has become detached.  

low density lipoprotein (LDL) - a blood substance with large amounts of cholesterol.

lower (gastrointestinal) GI series (Also called barium enema x-ray.) - x-rays of the rectum, colon, and lower part of the small intestine. 

lower back (Also called lumbar spine.) - a complex structure that connects the upper body to the lower body; consists of vertebrae, disks, spinal cord, and nerves.  

lower esophageal sphincter - muscle between the esophagus and stomach.

lumen - the hollow area within a tube.

lumpectomy - a surgical procedure in which only the tumor and a small area of surrounding tissue are removed.     

lung volume - the amount of air the lungs hold.

luteinizing hormone (LH) - hormone secreted by the pituitary gland in the brain that stimulates the growth and maturation of eggs in females and sperm in males.

lymph nodes (Also called lymph glands.) - small glands clustered in the neck, armpits, abdomen, and groin that supply infection-fighting cells to the bloodstream and filter out bacteria and other antigens.

lymphadenectomy - a procedure in which lymph nodes are taken from the body for purposes of diagnosing or staging cancer.

lymphatic system - tissues and organs, including bone marrow, spleen, thymus, and lymph nodes, that produce, store, and carry white blood cells to fight infection and disease.

lymphocyte - any one of a group of white blood cells of crucial importance to the adaptive part of the body's immune system.  

magnetic field therapy - using an alternating magnetic field to generate an electric current inside the tissues, resulting in changes to blood flow.

magnetic resonance imaging (MRI) - a non-invasive procedure that produces two-dimensional view of an internal organ or structure, especially the brain and spinal cord.

malabsorption syndromes - conditions that happen when the small intestine cannot absorb nutrients from foods.

malignant tumor - a mass of cancer cells that may invade surrounding tissues or spread to distant areas of the body.

mallet finger - common condition due to the rupture of the long extensor tendon of the finger.

malocclusion - an orthodontic problem that means "bad bite," including crowded, missing, or crooked teeth, extra teeth, or a misaligned jaw.

mammogram - a low-dose x-ray of the breast.

manometry - tests that measure muscle pressure and movements in the gastrointestinal (GI) tract.

massage - mechanical form of therapy in which the soft tissues are made more pliable with different techniques, promoting increased blood flow and subsequent healing.

mast cells - cells, which synthesize and store histamines, found in most body tissues, particularly just below the epithelial surfaces, serous cavities and around blood vessels.

mastitis - infection of the milk ducts in the breast.

mastoid - back portion of the temporal bone behind the ear.   

mastoid surgery - surgical procedure to remove an infection from the mastoid bone.

mean blood pressure - average blood pressure, taking account of the rise and fall that occurs with each heartbeat. It is often estimated by multiplying the diastolic pressure by two, adding the systolic pressure, and then dividing this sum by three.

median nerve - large nerve, comprising segments from the cervical spine, that is involved in neural function of the upper limb; commonly entrapped in the carpal tunnel of the wrist, to create carpal tunnel syndrome.

melanocytes - cells in the skin that produce and contain the pigment called melanin.

melena - blood in the stool.

meniscus - a part of the cartilage in the knees and other joints.  

micrographia - a change in handwriting with the script becoming smaller and more cramped.

middle ear - part of the ear that includes the eardrum and three tiny bones of the middle ear, ending at the round window that leads to the inner ear.

minimally invasive surgery - any technique involved in surgery that does not require a large incision. (See also endoscopy, abdominoscopy, or laparoscopy.)

miosis - constriction of the pupil.

misarticulation - inaccurately produced speech sound (phoneme) or sounds.

miscarriage - spontaneous termination of a pregnancy before the fetus has developed enough to survive outside the uterus.

mitral valve - the valve that controls blood flow between the left atrium and left ventricle in the heart.

modified radical mastectomy - the removal of the breast, some lymph nodes in the armpit, and sometimes part of the chest wall muscles.

motility - movement of food through the digestive tract.

motion sickness - dizziness, sweating, nausea, vomiting, and generalized discomfort experienced when an individual is in motion.

motor speech disorders - group of disorders caused by the inability to accurately produce speech sounds (phonemes).

moxibustion - the burning of herbal leaves on or near the body.

mucosal lining - lining of gastrointestinal (GI) tract organs that makes mucus.

mucosal protective drugs - medicines that protect the stomach lining from acid.

mucous colitis - see irritable bowel syndrome (IBS).

mucus - clear liquid made by the intestines that coats and protects tissues in the gastrointestinal tract.

multifidus - deep lumbar spine muscle that stabilizes the lumbar spine.

murmur - a blowing or rasping sound heard while listening to the heart; may or may not indicate problems within the heart or circulatory system.    

musculoskeletal system - the complex system that includes the bones, joints, ligaments, tendons, muscles, and nerves.

mycoplasma - very common sexually transmitted disease or urinary tract infection caused by a bacteria-like organism in the urethra and reproductive system.

mydriasis - dilation of the pupil.

myelogram - a specific x-ray study that uses an injection of a dye or contrast material into the spinal canal to allow careful evaluation of the spinal canal and nerve roots.

myocardial infarction (Also called heart attack.) - occurs when one of more regions of the heart muscle experience a severe or prolonged decrease in oxygen supply caused by a blocked blood flow to the heart muscle.

myocardial ischemia - insufficient blood flow to part of the heart.

myocardium - the muscle wall of the heart.

myoclonus - jerking, involuntary movements of the arms and legs; may occur normally during sleep.  

myofascial pain - the most common form of temporomandibular disorder; discomfort or pain in the muscles that control jaw function and the neck and shoulder muscles.

myomectomy - surgical procedure done to remove fibroids from the uterus while leaving the uterus intact.

myopia - nearsightedness.

near point of accommodation - the closest point in front of the eyes that an object may be clearly focused.  

near point of convergence - the maximum extent the two eyes can be turned inward.

needle aspiration (of the breast) - uses a thin needle and syringe to collect tissue or drain a lump after using a local anesthetic.

needle biopsy - biopsy procedure in which a small sample of tissue is removed through a hollow needle.

neoadjuvant therapy - chemotherapy given before surgery or radiation therapy.

nephrectomy - surgical removal of the kidney.  

nephropathy - diabetic kidney disease.

nerve conduction test - procedure to determine nerve impulse generation.

nerve sparing technique - a surgical technique often used during a radial prostatectomy in which one or both of the neurovascular bundles controlling erections are spared.

neural mobilization - techniques by which neural tissues are moved, either by movement relative to their surroundings or by tension development.

neural plasticity - ability of the brain and/or certain parts of the nervous system to change in order to adapt to new conditions, such as an injury.

neural prostheses - devices that substitute for an injured or diseased part of the nervous system to enhance the function.

neural stimulation - to activate or energize a nerve through an external source.

neural tube defect - type of birth defect, such as spina bifida, that results from failure of the spinal cord or brain to develop normally in a fetus.

neuralgia - a painful condition caused by disorders of the nervous system. 

neuritis - inflammation of a nerve or nerves.

neurofibromatosis (Von Recklinghausen's) - a group of inherited disorders in which noncancerous tumors grow on several nerves that may include the hearing nerve.

neurogenic - of nerve origin.

neurogenic communication disorder - inability to exchange information with others because of hearing, speech, and/or language problems caused by impairment of the nervous system.

neuron - a cell specialized to conduct and generate electrical impulses and to carry information from one part of the brain to another.

neuropathology - the study of the nervous system.  

neurotransmitters - chemical substances that carry impulses from one nerve cell to another; found in the space (synapse) that separates the transmitting neuron's terminal (axon) from the receiving neuron's terminal (dendrite).

Nissen fundoplication - operation to sew the top of the stomach (fundus) around the esophagus; used to stop stomach contents from flowing back into the esophagus (reflux) and to repair a hiatal hernia.

noise-induced hearing loss - hearing loss that is caused either by a one-time or repeated exposure to very loud sound(s).

noninvasive procedures - a diagnostic effort or treatment that does not require entering the body or puncturing the skin.

non-steroidal anti-inflammatory drugs (NSAIDs) - medications that produces antipyretic, analgesic, and anti-inflammatory effects.

nonulcer dyspepsia - constant pain or discomfort in the upper gastrointestinal tract.

norepinephrine - a neurotransmitter found mainly in areas of the brain that are involved in governing autonomic nervous system activity, especially blood pressure and heart rate.

Norwalk virus - virus that may cause gastrointestinal (GI) infection and diarrhea. (See also gastroenteritis.)

nuclear medicine - a specialized area of radiology that uses very small amounts of radioactive substances to examine organ function and structure.

nutrients - proteins, carbohydrates, fats, vitamins, and minerals provided by food and necessary for growth and the maintenance of life.

obstruction - blockage in the gastrointestinal tract that prevents the flow of liquids or solids.

occluded artery - an artery that is narrowed by plaque that impedes blood flow.

occult - disease or symptoms that are not readily detectable by physical examination or laboratory tests.

occult bleeding - blood in stool that is not visible to the naked eye.

ocular hypertension - high (greater than 21 mm Hg) intraocular pressure.

odorant - substance that stimulates the sense of smell.

olfaction - the act of smelling.

olfactometer - device for estimating the intensity of the sense of smell.

oncogenes - genes that promote normal cell division.

oncologist - a physician who specializes in treating cancer, including surgical oncologist, radiation oncologist, pediatric oncologist, gynecologic oncologist, and medical oncologist. 

oophorectomy - surgery to remove one or both ovaries.

open surgery - cutting the skin and tissues during surgery to expose a full view of the structures and organs involved in the procedure.

optional surgery - an operation the patient chooses to have done, which may not be essential to the continuation or quality of life. (See also elective surgery.)

oral and maxillofacial surgeon - orthopaedic facial surgeon who is responsible for treating a wide variety of dental problems, including the removal of impacted teeth and reconstructive facial surgery.

oral dissolution therapy - method of dissolving cholesterol gallstones.

orchiectomy (Also called castration.) - the surgical removal of the testicles.

oropharynx - the part of the throat at the back of the mouth.

orthodontics - orthodontics is the dental specialty that focuses on the development, prevention, and correction of irregularities of the teeth, bite, and jaw.

orthokeratology - the use of contact lenses to change the shape of the cornea in order to correct refractive error.

orthopaedic surgery (Also called orthopaedics.) - the medical specialty devoted to the diagnosis, treatment, rehabilitation, and prevention of injuries and diseases of the body's musculoskeletal system.

orthostatic hypotension - a large decrease in blood pressure upon standing; may result in fainting.    

osteoblast - cell found in bone; its function is to form the tissue and minerals that give bone its strength. 

osteoclast - very large cell formed in bone marrow; its function is to absorb and remove unwanted tissue.

osteocyte - cell found within the bone; its function is to help maintain bone as living tissue.

osteophyte - an outgrowth of bone.

otolaryngologist - physician/surgeon who specializes in diseases of the ears, nose, throat, head, and neck.

otologist - physician/surgeon who specializes in diseases of the ear.

otosclerosis - abnormal growth of bone in the inner ear, which prevents structures within the ear from working properly, resulting in a gradual loss of hearing.  

ototoxic drugs - drugs that can damage the hearing and balance organs located in the inner ear.    

outer ear - external portion of the ear, consisting of the pinna, or auricle, and the ear canal.

outpatient surgery - surgery which allows the patient to go home the same day.

ovaries - pair of small glands, located on either side of the uterus, in which egg cells develop and are stored and the female sex hormones estrogen and progesterone are produced.

overflow incontinence - the leakage of small amounts of urine from a bladder that is always full.

ovulation - release of a mature egg from an ovary.

oxytocin - hormone produced by the pituitary gland that stimulates contractions of the uterus during labor and release of milk during breastfeeding.

pacemaker - an electronic device that is surgically implanted into the patient's heart and chest to regulate heartbeat.

pain threshold - the point at which a stimulus causes a feeling of pain.

palliative treatment - therapy that relieves symptoms, such as pain, but does not alter the course of the disease; its primary purpose is to improve the quality of life.

pallidotomy - a surgical procedure in which a part of the brain, called the globus pallidus, is lesioned in order to improve symptoms of tremor, rigidity, and bradykinesia.

palming - an imaging technique involving the visualization of color.

palpitation - sensation of rapid heartbeats.

palsy - paralysis of a muscle or group of muscles.

pancreas - long gland that lies behind the stomach; manufactures insulin and digestive enzymes.

papillary stenosis - condition in which the openings of the bile ducts and pancreatic ducts narrow.

parietal cells - cells in the stomach wall that make hydrochloric acid.

parkinsonism - the name given to a group of disorders with similar features including four primary symptoms: tremor, rigidity, postural instability, and bradykinesia, that are the result of the loss of dopamine-producing brain cells.

parosmia - any disease or perversion of the sense of smell, especially the subjective perception of odors that do not exist.

partial colectomy - the removal of part of the large intestine.

partial mastectomy - surgery to remove a portion of the breast.

patellar tendonitis - inflammatory condition of the patellar ligament, usually due to overuse.

pathologist - physician who identifies diseases by studying cells and tissues under a microscope.

pathology - the study of diseases.

peak torque - measure of isokinetic performance.

pelvic exam - a physician examination of the uterus, vagina, ovaries, fallopian tubes, bladder, and rectum.

pelvic lymph node dissection - removal of some lymph nodes from the pelvis.

pepsin - enzyme made in the stomach that breaks down proteins.

peptic - related to the stomach and the duodenum, where pepsin is present.

peptic ulcer - sore in the lining of the esophagus, stomach, or duodenum, usually caused by the bacterium Helicobacter pylori. An ulcer in the stomach is a gastric ulcer; an ulcer in the duodenum is a duodenal ulcer.

perception - process of knowing or being aware of information through the ear.

perfusion - flow.

perianal - area around the anus.

pericardium - the membrane that surrounds the heart.

perilymph fistula - leakage of inner ear fluid to the middle ear that occurs without apparent cause or is associated with head trauma, physical exertion, or barotrauma.

perineal - related to the perineum.

perineum - area between the anus and the sex organs.

periodontal diseases (Also called gum diseases.) - serious bacterial infections that destroy the gums and the surrounding tissues of the mouth.

periodontist - a specialist in the field of dentristy responsible for the care and prevention of gum-related diseases, guided bone regeneration, and dental implants.

periostitis (Also called shin splints.) - inflammatory condition of the covering of the bones.

peritoneal adhesions - the peritoneum is a two-layered membrane that lines the wall of the abdominal cavity and covers abdominal organs. Sometimes organs begin to adhere to the peritoneum, requiring surgery to free the organs again.

peritoneum - lining of the abdominal cavity.

pessary - rubber or plastic device that is inserted through the vagina to help hold the uterus in place in women who have prolapse of the uterus.

Phalen's test - test for carpal tunnel syndrome in which the wrists are flexed for one minute.

pharynx - space behind the mouth that serves as a passage for food from the mouth to the esophagus and for air from the nose and mouth to the larynx.

phonology - study of speech sounds.

photophobia - sensitivity to light.

photorefractive keratectomy (PRK) - surgical procedure using an excimer laser to change the shape of the cornea.

physiatrist - the physician who specializes in physical medicine and rehabilitation.

pituitary gland - gland at the base of the brain that secretes hormones and regulates and controls other hormone-secreting glands and many body processes, including reproduction.

placenta - organ that develops in the uterus during pregnancy; links the blood supplies of a pregnant woman to the fetus to provide nutrients and remove waste products.

placental abruption - premature detachment of the placenta from the wall of the uterus causing severe bleeding that is life threatening to both a pregnant woman and fetus.

plantar warts - warts that occur on the sole of the foot and look like calluses; often a result of an infection or a specific virus.

plasma - the watery, straw-colored fluid which carries the cellular elements of the blood through circulation.

platelets - cells found in the blood.

pneumonectomy - removal of an entire lung, for cancer, lung abscesses, bronchiectasis, or extensive tuberculosis.

polyp - a growth that projects from the lining of mucous membrane, such as the intestine.

polyposis - presence of many polyps.

polyunsaturated fat - a type of fat found in vegetable oils and margarines that does not appear to raise blood cholesterol levels.

portal hypertension - abnormally high blood pressure in the portal vein, which supplies the liver with blood from the intestine.

portal vein - large vein that carries blood from the intestines and spleen to the liver.

positron emission tomography (PET) - a nuclear scanning procedure that gives a three-dimensional picture of the heart to provide information about the flow of blood through the coronary arteries to the heart muscle.

post-anesthesia care unit (Also called recovery room.) - the area a patient is brought to after surgery to recover.

postcholecystectomy syndrome (Also called biliary dyskinesia.) - condition that occurs after a gallbladder removal in which the muscle between the gallbladder and the small intestine does not work properly, causing pain, nausea, and indigestion.

posterior optical segment - portion of the eye located behind the crystalline lens; includes the vitreous, choroid retina, and optic nerve.

postgastrectomy syndrome - condition that occurs after an operation to remove the stomach (gastrectomy). (See also dumping syndrome.) 

postvagotomy stasis - delayed stomach emptying; often occurs after surgery on the vagus nerve.

prednisolone - one type of corticosteroid medication, usually used for inflammation.  

presbycusis - loss of hearing that gradually occurs because of changes in the inner or middle ear in individuals as they grow older.

preterm labor - labor that begins before the 37th week of pregnancy.

prick skin test - a test to determine if a person is allergic to certain substances. A physician places a drop of the substance being tested on the persons forearm or back and pricks the skin with a needle, allowing a tiny amount to enter the skin. If the person is allergi

primary sclerosing cholangitis - inflammation, scarring, and narrowing of the bile ducts inside and outside the liver.

proctalgia fugax - intense pain in the rectum that occasionally happens at night; caused by muscle spasms around the anus.

proctectomy - operation to remove the rectum.

proctocolectomy (Also called coloproctectomy.) - operation to remove the colon and rectum.

proctocolitis - inflammation of the colon and rectum.

proctologist - physician who specializes in disorders of the anus and rectum.

proctoscopy - looking into the rectum and anus with a proctoscope.

proctosigmoiditis - inflammation of the rectum and the sigmoid colon.

progestin - synthetic form of the female sex hormone progesterone.

prognosis - a prediction of the course of the disease.

prolapse - condition that occurs when a body part slips from its normal position.

prostatalgia - pain in the prostate gland.

prostate acid phosphatase (PAP) - an enzyme produced by the prostate that is elevated in some patients when prostate cancer has spread beyond the prostate.  

prostatectomy - surgical procedure for the partial or complete removal of the prostate.   

prostatism - any condition of the prostate that causes interference with the flow of urine from the bladder.

prostatitis - an inflamed condition of the prostate gland that may be accompanied by discomfort, pain, frequent urination, infrequent urination, and, sometimes, fever.

pruritus ani - itching around the anus.  

pubic symphysis - anterior joint of the pelvis.

pudendal block - pain-relieving procedure used during childbirth in which an anesthetic is injected into tissues surrounding the pudendal nerves on either side of the vagina; blocks pain in the tissues between the vagina and anus.

pulmonary - pertains to lungs and respiratory system.   

pulmonary artery - blood vessel delivering oxygen-poor blood from the right ventricle to the lungs. 

pulmonary hypertension - abnormally high blood pressure in the arteries of the lungs.

pulmonary vein - the vessel that carries newly oxygenated blood to the heart from the lungs.

pupil - the dark center in the middle of the iris through which light passes to the back of the eye.

pupillary response - the constriction or dilation of the pupil as stimulated by light.

pyloric sphincter - muscle between the stomach and the small intestine.

pylorus - opening from the stomach into the top of the small intestine (duodenum).

radial keratotomy - a surgical procedure in which incisions are made into the epithelium of the cornea to correct refractive error.

radiation - use of high-energy radiation from x-rays, neutrons, and other sources to kill cancer cells and shrink tumors.

radical mastectomy - surgical removal of the entire breast, the pectoral muscles, and the ancillary lymph nodes.

radical prostatectomy - surgery to remove the prostate along with the two seminal vesicle glands attached to the prostate.    

radical retropubic prostatectomy - an operation to remove the entire prostate gland and seminal vesicles through the lower abdomen.

radiculopathy - pinched nerve usually from a herniated, or slipped, disk; can cause a shooting pain often described as an electrical feeling.

radioisotope - a radioactive material injected into the body so that a nuclear scanner can make pictures.

radionuclide scan - an imaging scan in which a small amount of radioactive substance is injected into the vein. A machine measures levels of radioactivity in certain organs, thereby detecting any abnormal areas or tumors.

radionuclide ventriculography - a diagnostic procedure used to determine the shape and size of the heart's chambers.

range of motion - measurement of the extent to which a joint can go through all of its normal range of movements.

rectal manometry - test that uses a thin tube and balloon to measure pressure and movements of the rectal and anal sphincter muscles.

rectocele - condition in which weakening of the lower vaginal wall causes the rectum to bulge into the vagina.

rectum - lower end of the large intestine, leading to the anus.

reflex sympathetic dystrophy (RSD) - caused by an abnormal sympathetic muscle reflex, giving rise to a response that is out of proportion to, and inconsistent with, the injury.

reflux (Also called regurgitation.) - condition that occurs when gastric juices, or small amounts of food from the stomach, flow back into the esophagus and mouth.

reflux esophagitis - irritation of the esophagus due to stomach contents flowing back into the esophagus.

refractive error - the degree to which light reaches the back of the eye; includes myopia, hyperopia, and astigmatism.

regional anesthetic - an anesthetic used to numb a portion of the body.

regional enteritis - see Crohn's disease.

rehabilitation - the process of restoring a part of the body or a person to near-normal functioning after an injury or disease. 

required surgery - an operation which is necessary to continue quality of life. Required surgery may not have to be done immediately, like emergency surgery.

respiration - gas exchange from air to the blood and from the blood to the body cells.   

respiratory system - the group of organs responsible for carrying oxygen from the air to the bloodstream and for expelling carbon dioxide.   

resting tremor - a tremor of a limb that increases when the limb is at rest.

retching - dry vomiting.

retrolisthesis - posterior slippage of one vertebra onto another.

rheumatic fever - a childhood disease that may damage the heart valves or the outer lining of the heart.

rhinitis - an inflammation of the mucous membrane that lines the nose; often due to allergy to pollen, dust, or other airborne substances; causes sneezing, itching, a runny nose, and nasal congestion.

RICE (rest, ice, compression, and elevation) - treatment plan for acute injury to prevent inflammatory processes from becoming uncontrolled and to speed up the recovery process by eliminating swelling; acute injury management.

rigidity - increased resistance to the passive movement of a limb.

rotator cuff - muscles and their insertional tendons that form a cuff over the shoulder joint, on their way to attaching from the scapula to the humorous; major function is to control, and produce, rotation of the shoulder.

round window - membrane separating the middle ear and inner ear.

rupture - break or tear in any organ or soft tissue. 

sacro-iliac joint - synovial joint formed between the medial surface of the ilium and the lateral aspect of the upper sacral vertebrae; a fibrous joint, comprising and surrounded by very strong ligamentous structures; major function is to transmit body weight, but also has a

saline solution - a solution containing sodium chloride.

saliva - mixture of water, protein, and salts that makes food easy to swallow; begins digestion.

salpingectomy - surgical removal of one or both fallopian tubes.

scapula - commonly known as the shoulder blade.

sciatica - traditionally defined as pain in the sciatic nerve, or its branches, that is caused by direct pressure or irritation.

sclerotherapy - method of stopping upper gastrointestinal bleeding. A needle is inserted through an endoscope to bring hardening agents to the place that is bleeding.

scotoma - an area of partial or complete loss of vision surrounded by an area of normal vision.

sebum - oily substance produced by sebaceous glands in the skin.  

secretin - hormone made in the duodenum; causes the stomach to make pepsin, the liver to make bile, and the pancreas to make digestive juices.

segmental mastectomy - surgery to remove a portion of the breast.

sella turcica - bony structure that houses the pituitary gland.

sensorineural hearing loss - hearing loss caused by damage to the sensory cells and/or nerve fibers of the inner ear.  

septal defect - a hole in the wall of the heart.

septum - the muscle wall that divides the heart chambers.

serum - a clear fluid that separates when blood clots.

sesamoiditis - inflammatory condition affecting the two sesamoid bones in the flexor tendon of the great (big) toe.

sexually transmitted disease (STD) - infection spread through sexual intercourse and other intimate sexual contact.  

shigellosis - infection with the bacterium Shigella; usually causes a high fever, acute diarrhea, and dehydration. (See also gastroenteritis.)

shunt - a connector that allows blood flow between two locations.

Shwachman's syndrome - digestive and respiratory disorder of children in which certain digestive enzymes are missing and white blood cells are few.

sialorrhea - drooling.

sigmoid colon - lower part of the colon that empties into the rectum.

silent ischemia - ischemia not accompanied by chest pain.

simple mastectomy - surgical removal of the breast and possibly a few of the axillary lymph nodes close to the breast.

sinus (Also called paranasal sinuses.) - air cavities within the facial bones, lined by mucous membranes similar to those in other parts of the airways.

sinus node - the cells that produce the electrical impulses that cause the heart to contract.

slump test - a test for assessing the mobility of the pain-sensitive structures in the vertebral canal. 

small intestine - organ where most digestion occurs; measures about 20 feet and includes the duodenum, jejunum, and ileum.

smell - to perceive odor or scent through stimuli affecting the olfactory nerves.

smooth muscle - muscle that performs automatic tasks, such as constricting blood vessels.

soft-tissue - generally, the ligaments, tendons, and muscles in the musculoskeletal system.

somatosensory - refers to sensory signals from all tissues of the body including skin, viscera, muscles, and joints.

somatostatin - a hormone in the pancreas that helps tell the body when to make the hormones insulin, glucagon, gastrin, secretin, and renin.

spasm - a condition in which a muscle or group of muscles involuntarily contract.

spasmodic dysphonia - momentary disruption of the voice caused by involuntary movements of one or more muscles of the larynx (or voice box).

spastic colon - see irritable bowel syndrome (IBS).

speech - making definite vocal sounds that form words to express thoughts and ideas.

speech-language pathologist - health professional trained to evaluate and treat people who have voice, speech, language, or swallowing disorders, including hearing impairments, that affect their ability to communicate.

sphincter - ring-like band of muscle that opens and closes an opening in the body.

sphygmomanometer - the instrument used to measure blood pressure.

spinal anesthetic - an anesthetic which is injected into the spinal canal fluid for surgery in the lower abdomen, pelvis, rectum, or other lower extremities.

spinal instability - increased motion between vertebra, usually resulting from an injury; pain typically feels like tingling in the neck or arms.   

spine - a column in the body consisting of 33 vertebrae.

spirogram - record of the amounts of air being moved in and out of the lungs.

spleen - organ lying between the stomach and diaphragm that stores red blood cells and filters blood.

splenectomy - surgical removal of the spleen.

splenic flexure syndrome - condition that occurs when air or gas collects in the upper parts of the colon.

spondylosis - a condition of the spine involving a degenerative process.

sputum (Also called phlegm.) - mucous from the lungs.  

steatorrhea - condition in which the body cannot absorb fat.

stenosis - the narrowing or constriction of a blood vessel or valve in the heart.

stereopsis - ability to perceive three-dimensional depth.

sternum - the breastbone.

stethoscope - the instrument used to listen to the heart and other sounds in the body.

stirrups - technique of ankle strapping using rigid tape placed on the ankle; medial to lateral adhering to the undersurface of the heel, mimicking a stirrup.   

stoma - opening in the abdomen that is created by an operation (ostomy); must be covered at all times by a bag that collects stool.

stomach - main organ of digestion which lies between the esophagus and the small intestine.

stool (Also called feces.) - solid wastes that pass through the rectum as bowel movements. Stools are undigested foods, bacteria, mucus, and dead cells.

streptokinase - a clot-dissolving medication.

stress - mental or physical tension that results from physical, emotional, or chemical causes.

stress fracture - fracture caused by non-traumatic, cumulative overload on a bone; caused by a number of factors including overtraining, incorrect biomechanics, fatigue, hormonal imbalance, poor nutrition, and osteoporosis.

stress incontinence - involuntary leaking of urine which may be caused by coughing or straining.

stress ulcer - upper gastrointestinal ulcer from physical injury such as surgery, major burns, or critical head injury.

striatum - part of the basal ganglia; a large cluster of nerve cells, consisting of the caudate nucleus and the putamen, that controls movement, balance, and walking; the neurons of the striatum require dopamine to function.

stricture (Also called stenosis.) - abnormal narrowing of a body opening. (See also esophageal stricture and pyloric stenosis.)

subchondral tissue - the smooth tissue at the ends of bones, which is covered with another type of tissue (called cartilage).

Sudeck's atrophy - condition characterized by severe pain, swelling, and disability; commonly seen in the foot, but may occur in other joints of the lower limb.

superior vena cava - the large vein that returns blood to the heart from the head and arms.

surgery - operation to remove or repair a part of the body, or to find out if disease is present.

suspensory ligament of lens - a series of fibers that connect the ciliary body of the eye with the lens, holding it in place.

sustention tremor (Also called postural tremor.) - a tremor of a limb that increases when the limb is stretched.

synapse - a tiny gap between the ends of nerve fibers across which nerve impulses pass from one neuron to another; at the synapse, an impulse causes the release of a neurotransmitter, which diffuses across the gap and triggers an electrical impulse in the next neuron.

syncope - light-headedness or fainting caused by insufficient blood supply to the brain.

synovitis - inflammation of the synovial membrane, the tissue that lines and protects the joint.

synovium - a fibrous envelope that produces a fluid that helps to reduce friction and wear in a joint.

systemic treatment (Also called systemic therapy.) - treatment or therapy that reaches and affects cells throughout the body.

systolic blood pressure - the highest pressure to which blood pressure rises with the contraction of the heart.

tachycardia - rapid heart beat.

tachypnea - rapid breathing.

tamoxifen - an anticancer drug used in hormone therapy to block the effects of estrogen.

taste - sensation produced by a stimulus applied to the gustatory nerve endings in the tongue; the four tastes include: salt, sour, sweet, and bitter; some say there is a fifth taste described as savory.

taste buds - groups of cells located on the tongue that enable one to recognize different tastes.

technetium bone scan - radiological investigation to detect stress fractures.

telemetry unit - a small transmitter with wires that attach ECG patches to the chest that is used to send information about the heart, via radio transmission, to healthcare professionals for evaluation.

temporal arteries - vessels located over the temples on each side of the head that supply blood to part of the head.

tendon - a cord that connects muscle to bone or other tissue.

tendonitis - inflammation of a tendon or of the tendon covering; usually caused by not just a single injury, but a series of small stresses that repeatedly aggravate the tendon.

thallium stress test - a study in which radioactive potassium is carried by the blood; the progress is followed by x-ray pictures.

Thomas's test - examination to detect a fixed hip deformity.

thoracotomy - surgery to view the lung (that may be used to confirm cancer), or for chest trauma (to detect the source of bleeding).

throat disorders - disorders or diseases of the larynx (voice box) or esophagus.

thrombolysis - the breaking up of a blood clot.

thrombolytic drugs - medications used to dissolve blood clots.

thrombosis - an abnormal condition in which a blood clot develops in the blood vessel or in the heart.

thrombus - a blood clot.

thyroplasty (Also called laryngeal framework surgery.) - surgical technique to improve the voice by altering the cartilages of the larynx.

tibia - shin bone.

tinnitus - sensation of a ringing, roaring, or buzzing sound in the ears or head; often associated with various forms of a hearing impairment.

tissue - group or layer of cells that together perform specific functions.

tomography - from the Greek words "to cut or section" (tomos) and "to write" (graphein); in nuclear medicine, it is a method of separating interference from the area of interest by imaging a cut section of the object.

tongue - large muscle on the floor of the mouth that manipulates food for chewing and swallowing; the main organ of taste; assists in forming speech sounds.

total gastrectomy - complete removal of the stomach.

total hysterectomy - the removal of the uterus, including the cervix; the fallopian tubes and the ovaries remain.

Tourette syndrome - neurological disorder characterized by recurring movements and sounds (called tics).   

transesophageal echocardiography (TEE) - a diagnostic test that is used to measure the sound waves that bounce off of the heart.

transient ischemic attack (TIA) - a stroke-like event that lasts for a short period of time caused by a blocked blood vessel.

transplantation - replacing a damaged organ with one from a donor.

transurethral surgery - surgery in which no external incision is needed; the surgeon reaches the prostate by inserting an instrument through the urethra.

transvaginal ultrasound (Also called ultrasonography.) - an ultrasound test using a small instrument, called a transducer, that is placed in the vagina.

transverse colon - part of the colon that extends across the abdomen from right to left.

Trendelenburg gait - intrinsic disorder of the abductors of the hip, due to either a weakness or an inhibition to function; hip abductors are unable to stabilize the hip, as body weight is transferred to the affected side, resulting in a pelvic drop or tilt towards the opposi

tricuspid valve - the heart valve that controls blood flow from the right atrium into the right ventricle.

trigger finger - an irritation of the digital sheath that surrounds the flexor tendons of the finger. When the tendon sheath becomes thickened or swollen, it pinches the tendon and prevents it from gliding smoothly. In some cases, the tendon catches and then suddenly rele

trigger point - hypersensitive area or site in muscle or connective tissue; usually associated with myofascial pain syndromes.

trimester - a period of three months.

type 1 diabetes (Also called insulin dependent diabetes.) - a condition in which the pancreas produces so little insulin that the body cannot use blood glucose as energy; which must be controlled with daily insulin injections.

type 2 diabetes (Also called non-insulin dependent diabetes.) - a condition in which the pancreas produces so little insulin that the body cannot use the blood glucose as energy; can often be controlled through meal plans and physical activity plans, and diabetes pills or insulin.

tyrosine - the amino acid from which dopamine is made.

ulcer - sore on the skin surface or on the stomach lining.

ultraviolet radiation - invisible rays that come from the sun. UV radiation can damage the skin and cause melanoma and other types of skin cancer.

upper GI endoscopy - examining into the esophagus, stomach, and duodenum with an endoscope. (See also endoscopy.)

upper limb tension test (ULTT) - test to assess pain.

urea breath test - test used to detect Helicobacter pylori infection. The test measures breath samples for urease, an enzyme H. pylori produces.

ureters - two tubes that carry urine from the kidneys to the bladder.

urethra - narrow channel through which urine passes from the bladder out of the body.

urge incontinence - the inability to hold urine long enough to reach a restroom.

urgent surgery - an operation performed immediately as a result of an urgent medical condition. (See also emergency surgery.)

urinary retention - the inability to empty the bladder.

Usher's syndrome - a hereditary disease that affects hearing and vision.

uterus (Also called the womb.) - the uterus is a hollow, pear-shaped organ located in a woman's lower abdomen, between the bladder and the rectum, that sheds its lining each month during menstruation and in which a fertilized egg implants and grows into a fetus.

vaginal hysterectomy - the uterus is removed through the vaginal opening.

vaginosis, bacterial - very common vaginal infection characterized by symptoms such as increased vaginal discharge or itching, burning, or redness in the genital area.

vagotomy - operation to cut the vagus nerve, which causes the stomach to produce less acid.

vagus nerve - nerve in the stomach that controls the production of stomach acid.

valve - fold in the lining of an organ that prevents fluid from flowing backward.

valves, heart - (the heart valves are tricuspid, pulmonic, mitral, and aortic) - the "doors" between the chambers of the heart.

valvuloplasty - repairing a heart valve.

varices - stretched veins such as those that form in the esophagus from cirrhosis.

varicose vein - an abnormally dilated vein, usually found in the legs.

vascular - pertaining to blood vessels.

vasodepressors - a medication that raises blood pressure.

vasodilator - agent that widens blood vessels.

vein - a blood vessel that carries blood from the body back into the heart.    

velocardiofacial syndrome - an inherited disorder characterized by cleft palate, heart defects, a characteristic facial appearance, minor learning problems, and speech and feeding problems.

ventilation - movement of air (gases) in and out of the lungs.

ventricle - one of the two pumping chambers of the heart; the right ventricle receives oxygen-poor blood from the right atrium and pumps it to the lungs through the pulmonary artery; the left ventricle receives oxygen-rich blood from the left atrium and pumps it to t

ventricular fibrillation - a condition in which the ventricles contract in rapid and unsynchronized rhythms and cannot pump blood into the body.

vestibular neuronitis - infection at the vestibular nerve.

vestibular system - system in the body that is responsible for maintaining the body's orientation in space, balance, and posture; regulates locomotion and other movements and keeps objects in visual focus as the body moves.

ventricular fibrillation - a condition in which the ventricles contract in rapid and unsynchronized rhythms and cannot pump blood into the body.

vestibular neuronitis - infection at the vestibular nerve.

vestibular system - system in the body that is responsible for maintaining the body's orientation in space, balance, and posture; regulates locomotion and other movements and keeps objects in visual focus as the body moves.

vestibule - bony cavity of the inner ear.

villi - tiny, finger-like projections on the surface of the small intestine that help absorb nutrients.

viral hepatitis - hepatitis caused by a virus. Five different viruses (A, B, C, D, and E) most commonly cause this form of hepatitis. Other rare viruses may also cause hepatitis. (See also hepatitis.)

vitrectomy - an operation to remove the blood that sometimes collects at the back of the eyes when a person has eye disease.

vitreous body - a clear, jelly-like substance that fills the center of the eye.

vocal cords (Also called vocal folds.) - muscularized folds of mucous membrane that extend from the larynx (voice box) wall; enclosed in elastic vocal ligament and muscle that control the tension and rate of vibration of the cords as air passes through them.

vocal tremor - trembling or shaking of one or more of the muscles of the larynx - resulting in an unsteady-sounding voice.

voice - sound produced by air passing out through the larynx and upper respiratory tract.

voice disorders - group of problems involving abnormal pitch, loudness, or quality of the sound produced by the larynx (voice box).

volvulus - twisting of the stomach or large intestine.

vomiting - release of stomach contents through the mouth.

watchful waiting (Also called expectant management.) - close monitoring of prostate cancer by a physician instead of immediate treatment.

watermelon stomach - parallel red sores in the stomach that look like the stripes on a watermelon.

wedge resection of the lung - a small, localized section of the lung is removed, often for a lung biopsy.

wen - sebaceous cyst that develops in the skin, especially the scalp.

wheezing - a whistling noise in the chest which occurs during breathing when the airways are compressed.

white blood cell - a type of cell in the immune system that helps the body fight infection and disease. White blood cells include lymphocytes, granulocytes, macrophages, and others.

whole blood - blood containing all its components, such as red and white blood cells, platelets, and more.

womb - the common term for uterus, a muscular organ inside which the baby grows during pregnancy

X chromosome - one of the two sex chromosomes; determines female sex characteristics

Xerophthalmia - Abnormal dryness and thickening of the mucous membrane lining of the eyelids and white part of the eye and cornea. Caused by vitamin-A deficiency or certain eye diseases.

Xerostomia - a dry mouth condition; can be caused by a number of things, including rheumatoid arthritis, diabetes, kidney failure, infection with HIV (the virus that causes AIDS), drugs used to treat depression, and radiation treatment for mouth or throat cancer.

Y chromosome - one of the two sex chromosomes; determines male sex characteristics

yeast infection - a term usually referring to a candidiasis infection; characterized by itching, burning, or redness of the vaginal area.

yellow fever - a life-threatening viral infection transmitted by mosquitoes that causes jaundice, fever, headache, and vomiting.

Zenker's diverticulum - pouches in the esophagus from increased pressure in and around the esophagus.

Zollinger-Ellison syndrome - Group of symptoms that occur when a tumor called a gastrinoma forms in the pancreas. The tumor releases large amounts of the hormone gastrin, which causes too much acid in the duodenum, resulting in ulcers, bleeding, and perforation.

zygote intrafallopian transfer (ZIFT) - method of treating infertility by removing eggs from a woman's ovaries, fertilizing them in the laboratory with sperm from her partner or a donor, and inserting one or more of the fertilized eggs into one of her fallopian tubes.