Anatomy, Zoology. the part of the body of a mammal between the thorax and the pelvis; belly. the cavity of this part of the body containing the stomach, intestines, etc. (in nonmammalian vertebrates) a region of the body corresponding to, but not coincident with, this part or cavity.
Entomology. the posterior section of the body of an arthropod, behind the thorax or the cephalothorax.
the region of the body of a vertebrate that contains the viscera other than the heart and lungs. In mammals it is separated from the thorax by the diaphragm
the front or surface of this region; belly related adjective coeliac
(in arthropods) the posterior part of the body behind the thorax, consisting of up to ten similar segments