1the front part of the human trunk below the ribs, containing the stomach and bowels: his fat belly stuck out over his trousers the stomach, especially as representing the body’s need for food:they’ll fight all the better on empty bellies the underside of a bird or other animal: grasses were said to have been tall enough to brush the bellies of horses (also belly pork) [mass noun] a cut of pork from the underside between the legs. a pig’s belly as food, especially as a traded commodity.
2the rounded underside of a ship or aircraft. the top surface of an instrument of the violin family, over which the strings are placed. 1swell or cause to swell: [no object]:as she leaned forward her pullover bellied out [with object]:the wind bellied the sail out
2 [no object]
(belly up to
) North American informal move or sit close to (a bar or table): regulars who first bellied up to the bar years before