interior mesenteric artery [L, inner; Gk, mesos, middle, enteron, intestine, arteria, airpipe] , a visceral branch of the abdominal aorta, arising just above the division into the common iliacs and supplying the left half of the transverse colon, all of the descending and iliac colons, and most of the rectum. It has left colic, sigmoid, and superior rectal branches.
