(anatomy) One of the nine areas that the abdomen is divided into. / Used other than figuratively or idiomatically: see abdominal, region.

(herpetology) Any of the riblike structures that cross the abdomen in lizards.

(ichthyology) One of the posterior paired fins of fishes; pelvic fin; ventral fin.

(herpetology) plural of abdominal rib

plural of abdominal fin

(ichthyology) A pair of sphincters near the cloaca that allow for communication between the abdominal cavity and the exterior.

(often in the plural) Any of a group of four muscles that form the abdominal wall.

(medicine) During childbirth, a technique in which the abdomen is surrounded by a chamber and has the pressure decreased intermittently, to assist the uterus in its task.

(medicine) A pregnancy outside of the uterus, and within the abdominal cavity.

plural of abdominal muscle