What does "flap" mean?

Flap: A hinged leaf, as of a table or shutter.

Additional senses

  1. 2.The motion of anything broad and loose, or a stroke or sound made with it; as, the flap of a sail or of a wing.
  2. 3.pl. (Far.) A disease in the lips of horses. Flap tile, a tile with a bent up portion, to turn a corner or catch a drip. -- Flap valve (Mech.), a valve which opens and shuts upon one hinged side; a clack valve.
  3. 4.To beat with a flap; to strike. Yet let me flap this bug with gilded wings. Pope.
  4. 5.To move, as something broad and flaplike; as, to flap the wings; to let fall, as the brim of a hat. To flap in the mouth, to taunt. [Obs.] W. Cartwright.
  5. 6.To move as do wings, or as something broad or loose; to fly with wings beating the air. The crows flapped over by twos and threes. Lowell.
  6. 7.To fall and hang like a flap, as the brim of a hat, or other broad thing. Gay.

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