n. That part of the human body which extends from the breast to the groin, and contains the bowels: the part of the trunk between the diaphragm and the pelvis, considered as to its front and side walls and its cavity and contents; the abdomen. See cut under abdomen.n. The part of any animal which corresponds to the human belly; the abdomen in general.n. The stomach with its adjuncts: as, a hungry belly.n. The womb.n. The fleshy part of a muscle, as distinguished from its tendinous portion: as, the anterior belly of the digastricus muscle.n. The hollow or interior of an inclosed place.n. The part of anything which resembles the belly in protuberance or cavity, as of a bottle, a tool, a sail filled by the wind, a blast-furnace, etc.n. In technology, the inner, lower, or front surface or edge of anything.To fill; swell out.To swell and become protuberant, like the belly; bulge out.