[flap] n [ME flappe] (14c) 1: a stroke with something broad: slap
2. obs: something broad and flat used for striking
3: something that is broad, limber, or flat and usu. thin and that hangs loose or projects freely: as a: a piece on a garment that hangs free b: a part of a book jacket that folds under the book's cover c: a piece of tissue partly severed from its place of origin for use in surgical grafting d: an extended part forming the closure (as of an envelope or carton)
4: the motion of something broad and limber (as a sail or wing)
5: a movable auxiliary airfoil usu. attached to an airplane wing's trailing edge to increase lift or drag--see airplane illustration
6. a: a state of excitement or agitation: tizzy, uproar b: something (as an incident or remark) that generates an uproar 7: a consonant (as the sound /d/ in ladder and /t/ in latter) characterized by a single rapid contact of the tongue or lower lip against another point in the mouth--called also tap
[2]flap vb flapped ; flap.ping vt (14c) 1: to beat with or as if with a flap
2: to toss sharply: fling
3: to move or cause to move in flaps ~ vi 1: to sway loosely usu. with a noise of striking and esp. when moved by wind
2. a: to beat or pulsate wings or something suggesting wings b: to progress by flapping c: to flutter ineffectively
3: to talk foolishly and persistently