n 1 a  :  the part of the body between the thorax and the pelvis with the exception of the back - called also belly   b  :  the cavity of this part of the trunk lined by the peritoneum, enclosed by the body walls, the diaphragm, and the pelvic floor, and containing the visceral organs (as the stomach, intestines, and liver)  c  :  the portion of this cavity between the diaphragm and the brim of the pelvis - compare PELVIC CAVITY   2  :  the posterior often elongated region of the body behind the thorax in arthropods .
 
     
 
Published under license with Merriam-Webster, Incorporated.  © 1997-2004.