Acetaminophen: a drug that reduces pain and fever, but not inflammation. It is sold under the brand name Tylenol.
Acute: abrupt onset that usually is severe; happens for a short period of time.
Adenoma: benign (non-cancerous) polyps, or growths, that are considered the first step toward colon and rectal cancer.
Adhesion: a band of scar tissue that connects two surfaces of the body that are normally separate.
Adjuvant therapy: additional treatment, or add-on treatment, provided with the primary treatment to prevent cancer recurrence.
Adverse effect: a negative or harmful effect.
Analgesic: medicine to relieve pain.
Anemia: a condition in which a person has a low red blood cell count. It occurs when there is not enough hemoglobin in a person's blood. Hemoglobin is the substance in the red blood cells that enables the blood to transport oxygen throughout the body.
Antibiotic: medication used to treat bacterial infections.
Antibodies: proteins produced by the body to protect itself from foreign substances, such as bacteria or viruses.
Antigens: substances that provoke an immune response in the body. The body produces antibodies to fight antigens, or harmful substances, to try to eliminate them.
Anti-inflammatory: medication used to reduce pain, swelling, or other irritation caused by inflammation.
Air contrast barium enema: also called double contrast barium enema -- an X-ray examination of the entire large intestine (colon) and rectum in which barium and air are introduced gradually into the colon by a rectal tube.
Anal fissure: a split or crack in the lining of the anal opening, usually caused by the passage of very hard or watery stools.
Anastomosis: a surgical joining of two ducts, blood vessels, or bowel segments to allow flow from one to the other.
Aneurysm: the abnormal enlargement or bulging of a blood vessel, caused by damage or weakness in the blood vessel wall.
Angiogram/Angiography: a technique that uses dye to highlight blood vessels.
Anoscopy: an examination of the anus with a short, metal or plastic scope. The anoscopy procedure is used to look for hemorrhoids, anal polyps, or other causes of bright-red rectal bleeding.
Anus: the opening of the rectum positioned in the fold between the buttocks, situated at one end of the digestive tract where waste is expelled.
APC: often referred to as a "tumor suppressor gene," APC is a gene that produces a protein to help slow down the rate at which cells divide and grow.
Asymptomatic: no symptoms; no clear evidence that disease is present.
Banding: a technique, used to study our genes, in which chromosomes are stained with fluorescent or chemical dyes to determine their characteristics.