Flutter  —v. 1 flap (the wings) in flying or trying to fly. 2 fall quiveringly (fluttered to the ground). 3 wave or flap quickly. 4 move about restlessly. 5 (of a pulse etc.) Beat feebly or irregularly. —n. 1 act of fluttering. 2 tremulous excitement (caused a flutter). 3 slang small bet, esp. On a horse. 4 abnormally rapid heartbeat. 5 rapid variation of pitch, esp. Of recorded sound. [old english]