1. scalelike structure between the base of the wing and the halter of a two-winged fly • Syn: calypter • Derivationally related forms: alular • Hypernyms: squama • Part Holonyms: fly 2. tuft of small stiff feathers on the first digit of a bird's wing • Syn: bastard wing, spurious wing • Derivationally related forms: alular • Hypernyms: feather, plume, plumage • Part Holonyms: wing