Definition of: flutter

(flut′ər) v.i.
1. To wave or flap rapidly and irregularly, as in the wind.
2. To flap the wings rapidly, in or as in erratic flight.
3. To move or proceed with irregular motion: to flutter to the ground.
4. To move about lightly and quickly; flit.
5. To be excited or nervous, as with hope, fear, or expectation.
—v.t.
6. To cause to flutter.
7. To excite; fluster. See synonyms under SHAKE.
—noun
1. The act of vibrating or quivering.
2. Agitation; confused or tumultous emotion.
3. An up-and-down motion of the feet used in various swimming strokes, especially the crawl.
4. Aeron. A periodic oscillation set up in any part of an airplane by mechanical disturbances and maintained by inertia, structural characteristics, etc.
5. Tremololike pulsations in the sound track of a motion picture, due to rapid fluctuations in motor speed.
6. Pathol. An abnormally rapid but rhythmical contraction of the atria of the heart; also auricular flutter. [OE flotorian]
—flut′ter·er noun
—flut′ter·y adjective