a chronic gastrointestinal ailment lacking a specific known cause, characterized by abdominal pain, cramps, and diarrhea: abbrev. IBS
See irritable bowel syndrome in American Heritage Dictionary 4
A chronic disorder characterized by motor abnormalities of the small and large intestines, causing variable symptoms including cramping, abdominal pain, constipation, and diarrhea. Also called irritable colon, spastic colon.