n. sing. & pl. [ OE. bely, below, belly, bellows, AS. bælg, bælig, bag, bellows, belly. Bellows is prop. a pl. and the orig. sense is bag. See Belly. ] An instrument, utensil, or machine, which, by alternate expansion and contraction, or by rise and fall of the top, draws in air through a valve and expels it through a tube for various purposes, as blowing fires, ventilating mines, or filling the pipes of an organ with wind. [ 1913 Webster ]

Bellows camera, in photography, a form of camera, which can be drawn out like an accordion or bellows. --
Hydrostatic bellows. See Hydrostatic. --
A pair of bellows, the ordinary household instrument for blowing fires, consisting of two nearly heart-shaped boards with handles, connected by leather, and having a valve and tube. [ 1913 Webster ]

(Zool.) A European fish (Centriscus scolopax), distinguished by a long tubular snout, like the pipe of a bellows; -- called also trumpet fish, and snipe fish. [ 1913 Webster ]