ulcerative colitis
(ul-sur-a-tiv cO-lI-tis)
A chronic disease of unknown cause characterized by ulceration of the colon and rectum, with rectal bleeding, abdominal pain, and diarrhea; frequently causes anemia and electrolyte imbalance, and is less frequently complicated by peritonitis inflammation of the abdominal membrane, toxic megacolon (a condition of extreme dilation and hypertrophy of the colon), or cancer of the colon.