[bel.lows] n pl but sing or pl in constr [ME belu, fr. OE belg--more at belly] (bef. 12c) 1: an instrument or machine that by alternate expansion and contraction draws in air through a valve or orifice and expels it through a tube; also: any of various other blowers
2: lungs
3: the pleated expansible part in a camera; also: a metallic or plastic flexible and expansible vessel