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definitions

flap

[flap]
See more synonyms for flap on Thesaurus.com
verb (used without object), flapped, flap·ping.
  1. to swing or sway back and forth loosely, especially with noise: A loose shutter flapped outside the window.
  2. to move up and down, as wings; flap the wings, or make similar movements.
  3. to strike a blow with something broad and flexible.
  4. Slang. to become excited or confused, especially under stress: a seasoned diplomat who doesn't flap easily.
verb (used with object), flapped, flap·ping.
  1. to move (wings, arms, etc.) up and down.
  2. to cause to swing or sway loosely, especially with noise.
  3. to strike with something broad and flat.
  4. to toss, fold, shut, etc., smartly, roughly, or noisily.
  5. Phonetics. to pronounce (a sound) with articulation resembling that of a flap: The British often flap their r's.
noun
  1. something flat and broad that is attached at one side only and hangs loosely or covers an opening: the flap of an envelope; the flap of a pocket.
  2. either of the two segments of a book jacket folding under the book's front and back covers.
  3. one leaf of a folding door, shutter, or the like.
  4. a flapping motion.
  5. the noise produced by something that flaps.
  6. a blow given with something broad and flat.
  7. Slang.
    1. a state of nervous excitement, commotion, or disorganization.
    2. an emergency situation.
    3. scandal; trouble.
  8. Surgery. a portion of skin or flesh that is partially separated from the body and may subsequently be transposed by grafting.
  9. Aeronautics. a movable surface used for increasing the lift or drag of an airplane.
  10. Phonetics.
    1. a rapid flip of the tongue tip against the upper teeth or alveolar ridge, as in the r-sound in a common British pronunciation of very, or the t-sound in the common American pronunciation of water.
    2. a trill.
    3. a flipping out of the lower lip from a position of pressure against the upper teeth so as to produce an audible pop, as in emphatic utterances containing f-sounds or v-sounds.
  11. Building Trades.
    1. Also called backflap hinge, flap hinge.a hinge having a strap or plate for screwing to the face of a door, shutter, or the like.
    2. one leaf of a hinge.

Origin of flap

1275–1325; Middle English flappe a blow, slap, flappen to hit, slap; compare Dutch flap, flappen
Related formsflap·less, adjectiveun·flap·ping, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for flap

turbulence, brouhaha, fuss, confusion, flail, flop, dangle, hang, vibrate, thrash, apron, hanging, fold, tag, tab, strip, skirt, overlap, adjunct, tail

Examples from the Web for flap

Contemporary Examples of flap

Historical Examples of flap

  • A five, a four and the main,' shouted the big man, with a voice like the flap of a sail.

    The White Company

    Arthur Conan Doyle

  • Anthony lifted the flap, holding up the lantern, and we both looked in.

    It Happened in Egypt

    C. N. Williamson

  • Oh, I wish you could have seen him flap his wings with delight.

  • Then he let down the flap, and examined the empty pigeon-holes and dusty panelling.

    The Golden Age

    Kenneth Grahame

  • I put gun and maps in the right pocket; food in that flap behind you.

    Under Arctic Ice

    H.G. Winter

British Dictionary definitions for flap

flap

verb flaps, flapping or flapped
  1. to move (wings or arms) up and down, esp in or as if in flying, or (of wings or arms) to move in this way
  2. to move or cause to move noisily back and forth or up and downthe curtains flapped in the breeze
  3. (intr) informal to become agitated or flustered; panic
  4. to deal (a person or thing) a blow with a broad flexible object
  5. (tr sometimes foll by down) to toss, fling, slam, etc, abruptly or noisily
  6. (tr) phonetics to pronounce (an (r) sound) by allowing the tongue to give a single light tap against the alveolar ridge or uvula
noun
  1. the action, motion, or noise made by flappingwith one flap of its wings the bird was off
  2. a piece of material, etc, attached at one edge and usually used to cover an opening, as on a tent, envelope, or pocket
  3. a blow dealt with a flat object; slap
  4. a movable surface fixed to the trailing edge of an aircraft wing that increases lift during takeoff and drag during landing
  5. surgery a piece of tissue partially connected to the body, either following an amputation or to be used as a graft
  6. informal a state of panic, distress, or agitation
  7. phonetics an (r) produced by allowing the tongue to give a single light tap against the alveolar ridge or uvula

Word Origin for flap

C14: probably of imitative origin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for flap
n.

mid-14c., flappe "a blow, slap," probably imitative of the sound of striking. Meaning "something that hangs down" is first recorded 1520s. Sense of "motion or noise like a bird's wing" is 1774; meaning "disturbance, noisy tumult" is 1916, British slang.

v.

early 14c., "dash about, shake;" later "strike, hit;" see flap (n.). Meaning "to swing loosely" is from 1520s. Related: Flapped; flapping.

Online Etymology Dictionary, © 2010 Douglas Harper
flap in Medicine

flap

[flăp]
n.
  1. Tissue used in surgical grafting that is only partially detached from its donor site so that it continues to be nourished during transfer to the recipient site.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.