Medical Terminology: Glossary 1

Abdomen

Space below the chest that contains organs such as the stomach, liver, intestines, and gallbladder. The abdomen lies between the diaphragm and the pelvis.

Abdominal

Pertaining to the abdomen.

Abdominal cavity

See ABDOMEN.

Ablation

Removal of abnormal tissue by surgical or mechanical means

Abnormal

Pertaining to being away (AB-) from the norm; irregular.

Acquired immunodeficiency syndrome or AIDS

Suppression or deficiency of the immune response caused by exposure to the HUMAN IMMUNODEFICIENCY VIRUS (HIV).

Acromegaly

Enlargement of extremities as a result of thickening of the bones and soft tissues; it is caused by excessive secretion of growth hormone from the pituitary gland (after completion of puberty).

Acute

Sharp, sudden, and intense for a short period of time.

Acute myocardial ischemia

Sudden decrease in blood flow to heart muscle.

Adenectomy

Removal of a gland.

Adenitis

Inflammation of a gland.

Adenocarcinoma

Cancerous tumor derived from glandular cells.

Adenoidectomy

Removal of the adenoids.

Adenoids

Enlarged lymphatic tissue in the upper part of the throat near the nasal passageways.

Adenoma

Benign tumor of glandular cells.

Adenopathy

Disease of glands. Often this term refers to enlargement of lymph nodes (which are not true glands, but collections of lymphatic tissue).

Adnexa uteri

Accessory structures of the uterus (ovaries and

Adrenal cortex

Outermost part of the adrenal gland. The adrenal cortex secretes steroid hormones such as GLUCOCORTICOIDS (cortisone).

Adrenal glands

Two endocrine glands, each above a kidney. The adrenal glands produce hormones such as adrenaline (epinephrine) and hydrocortisone (cortisol).

Adrenalectomy

Removal (excision) of adrenal glands.

Adrenaline

Hormone secreted by the adrenal glands. It is released into the bloodstream in response to stress, such as from fear or physical injury. Also called EPINEPHRINE.

Adrenocorticotropic hormone

Hormone secreted by the pituitary gland. It stimulates the adrenal gland (cortex or outer region) to secrete the hormone cortisone. Also called ACTH.

Adrenopathy

Disease of ADRENAL GLANDS. AIDS: See ACQUIRED IMMUNODEFICIENCY SYNDROME.

Air sacs

Thin-walled sacs within the lung. Inhaled oxygen passes into the blood from the sacs, and carbon dioxide passes out from the blood into the sacs to be exhaled.

Albumin

A large-molecule protein found in blood and tissues.

Albuminuria

Albumin (protein) in the urine; it indicates a malfunction of the kidney.

Alkaline phosphatase

An enzyme present in blood and body tissues, such as bone and liver. Elevated in diseases such as those of bone and liver. Also called alk phos.

Allergist

Medical doctor specializing in identifying and treating abnormal sensitivity to substances such as pollen, dust, foods, and drugs.

Alopecia

Loss of hair; baldness. ALT: Alanine transferase, an enzyme normally found in blood and tissues, especially the liver. ALT is elevated in liver disease. (Formerly called SGPT.)

ALT

alanine transferase, an enzyme normally found in blood and tissues, especially the liver. elevated in liver disease

Alveolar

Pertaining to air sacs (alveoli) within the lungs.

Alveolus

An air sac within the lung (plural: alveoli).

Alzheimer disease

Deterioration of mental capacity (irreversible dementia) marked by intellectual deterioration, disorganization of personality, and difficulties in carrying out tasks of daily living.

Amenorrhea

Absence of menstrual periods.

Amniocentesis

Surgical puncture to remove fluid from the amnion (sac surrounding the developing fetus).

Anal

Pertaining to the anus (opening of the rectum to the outside of the body).

Analgesic

Medication that reduces or eliminates pain.

Analysis

Separating a substance into its component parts.

Anastomosis

New surgical connection between two previously unconnected bowel parts, vessels, or ducts.

Androgen

Hormone that controls the development of masculine characteristics. An example is TESTOSTERONE.

Anemia

Deficiency of hemoglobin and/or in number of red blood cells, which results in reduced oxygen to body cells. Literally, anemia means lacking (AN-) in blood (-EMIA).

Anemic

Pertaining to ANEMIA.

Anesthesiologist

Medical doctor specializing in administering agents capable of bringing about loss of sensation and consciousness.

Anesthesiology

Study of how to administer agents capable of

Aneurysm

Localized widening of the wall of an artery, of a vein, or of the heart. From the Greek aneurysma, meaning "widening."

Angina

Sharp pain in the chest resulting from a decrease in blood supply to heart muscle. Also called angina pectoris (PECT/O means chest).

Angiography

X-ray recording of blood vessels after contrast is injected.

Angioplasty

Surgical repair of a blood vessel. A tube (catheter) is placed in a clogged artery and a balloon at the end of the tube is inflated to flatten the clogged material against the wall of the artery. This enlarges the opening of the artery so that more blood can pass through. Also called balloon angioplasty.

Angiotensin

Hormone that is a powerful vasoconstrictor and raises blood pressure.

Ankylosing spondylitis

Chronic inflammation of the vertebrae (backbones) with stiffening of spinal joints so that movement becomes increasingly painful.

Ankylosis

Stiffening and immobility of a joint caused by injury, disease, or a surgical procedure.

Anomaly

Irregularity; a deviation from the normal. A congenital anomaly (irregularity) is present at birth.

Antenatal

Before birth.

Antepartum

Before birth.

Anterior

Located in the front (of the body or of a structure).

Antiandrogen

Substance that inhibits the effects of androgens (male hormones).

Antiarrhythmic

Pertaining to a drug that works against or prevents abnormal heartbeats (arrhythmias).

Antibiotic

A chemical substance produced by various microorganisms or fungi (immature plants) that inhibits or destroys bacteria or other small organisms. Examples of antibiotics are penicillin and streptomycin. They are used in the treatment of infectious diseases.

Antibody

A substance that works against (ANTI-) germs ("bodies" of infection). Antibodies are produced by white blood cells when germs (antigens) enter the bloodstream.

Anticoagulant

Drug that prevents clotting (coagulation). Anticoagulants are given when there is danger of clot formation in blood vessels, as may happen after a heart attack.

Anticonvulsant

Drug that prevents or relieves convulsions (involuntary muscular contractions).

Antidepressant

Drug used to prevent or treat depression.

Antidiabetic

Drug that prevents or relieves symptoms of diabetes.

Antiestrogen

Substance that inhibits the effects of estrogens (female hormones).

Antifungal

Drug that destroys or inhibits the growth of fungi (organisms such as yeasts, molds, and mushrooms).

Antigen

Foreign protein (such as on a bacterium or virus) that stimulates white blood cells to make antibodies. Antigens are then destroyed by the antibodies.

Antihistamine

Drug used to counteract the effects of histamine production in allergic reactions and colds.

Antihypertensive

Drug that reduces high blood pressure.

Antitubercular

Agent or drug used to treat tuberculosis.

Antiviral

Agent that inhibits and prevents the growth and reproduction of viruses.

Anuria

Lack of urine formation by the kidney.

Anus

Opening of the rectum to the surface of the body; solid wastes (feces) leave the body through the anus.

Aorta

Largest artery, which leads from the lower left chamber of the heart to arteries all over the body.

Aortic stenosis

Narrowing of the aorta.

Apex

Pointed end of an organ (plural: apices [A-pih-seez]).

Aphakia

Absence of the lens of the eye.

Aphasia

Absence or impairment of communication through speech.

Apnea

Not (A-) able to breathe (-PNEA); temporary stoppage of breathing. In sleep apnea, during sleep, a person is momentarily unable to contract respiratory muscles and maintain air flow through the nose and mouth.

Appendectomy

Removal of the appendix.

Appendicitis

Inflammation of the appendix.

Appendix

Small sac that hangs from the juncture of the small and large intestines in the right lower quadrant of the abdomen. Its function is unknown.

Arachnoid membrane

The middle membrane of the MENINGES (coverings around the brain and spinal cord).

Areola

Dark, pigmented area around the nipple of the breast.

Arrhythmia

Abnormal heart rhythm.

Arteriography

Process of recording (x-ray) of arteries after injecting contrast material.

Arteriole

Small artery.

Arteriolitis

Inflammation of small arteries (arterioles).

Arteriosclerosis

Hardening of arteries. The most common form is atherosclerosis, which is hardening of arteries caused by collection of fatty, cholesterol-like deposits (plaque) in arteries.

Arteriovenous fistula

An abnormal communication between an artery and a vein. It can also be created surgically to provide access for hemodialysis.

Artery

Largest blood vessel. Arteries carry blood away from the heart.

Arthralgia

Pain in a joint.

Arthritis

Inflammation of a joint.

Arthrocentesis

Surgical puncture to remove fluid from a joint for diagnosis or treatment.

Arthrogram

X-ray record of a joint.

Arthropathy

Disease of joints.

Arthroplasty

Surgical repair of a joint, especially to restore mobility in osteoarthritis or rheumatoid arthritis.

Arthroscope

Instrument used to examine the inside of a joint.

Arthroscopy

Process of visual examination of a joint.

Arthrosis

Abnormal condition of a joint.

Ascites

Abnormal collection of fluid in the abdomen.