Etymology From Middle English flap, flappe (“a slap; blow; buffet; fly-flap; something flexible or loose; flap”), related to Saterland Frisian Flappert (“wing, flipper”), Middle Dutch flabbe (“a blow; slap on the face; fly-flap; flap”) (modern Dutch flap (“flap”)), Middle Low German flabbe, vlabbe, flebbe, from the verb (see below). Related also to English flab and flabby.
Anything broad and flexible that hangs loose, or that is attached by one side or end and is easily moved.
a flap of a garment
The envelope flap seemed curiously wrinkled.
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Again, Beside these parts destin'd to divers offices, there is a peculiar provision for the wind-pipe, that is, a cartilagineous flap upon the opening of the Larynx or Throttle, which hath an open cavity for the admiffion of the air1686, Sir Thomas Browne, chapter VIII, in The Works of the Learned Sr. Thomas Brown: Containing, Enquiries Into Vulgar and Common Errors, etc, book IV:
The hairs guide the pollinating insect to the base of the petal, where there is a purplish nectary covered by a flap of tissue.1998 October, Robert H. Mohlenbrock, “Twin Peaks”, in Natural History, volume 107, number 8, page 73:
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A hinged leaf.
the flaps of a table
the flap of a shutter
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Aeronautics, Aerospace, Aviation, Business, Engineering, Natural sciences, Physical sciences A hinged surface on the trailing edge of the wings of an aeroplane, used to increase lift and drag.
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A side fin of a ray.
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The motion of anything broad and loose, or a sound or stroke made with it.
the flap of a sail
the flap of a wing
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Then he commenced to talk, really talk. and inside of two flaps of a herring's fin he had me mesmerized, like Eben Holt's boy at the town hall show. He talked about the ills of humanity, and the glories of health and Nature and service and land knows what all.1913, Joseph C[rosby] Lincoln, chapter IV, in Mr. Pratt’s Patients, New York, N.Y.; London: D[aniel] Appleton and Company, →OCLC:
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A controversy, scandal, stir, or upset.
The comment caused quite a flap in the newspapers.
“[…] We saw him vanish right in front of the rest of us. He was there and then he wasn’t. We were to wait for a year for his return or for some message. We waited. Nothing.” / Calvin, his voice cracking: “Jeepers, sir. You must have been in sort of a flap.”1962, Madeleine L’Engle, “Absolute Zero”, in A Wrinkle in Time, New York, N.Y.: Ariel Books, →OCLC; republished New York, N.Y.: Ariel Books, 1973 printing, →ISBN, page 167:
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The current Middlesex grand jury […] is once again on the case, partly as the result of the public flap created by Brill's death and, of course, by the series of articles written by Corsetti in the month after Brill's demise.1980 April 19, Mitzel, “Barbre Murder Grand Jury: Puccini Outtake”, in Gay Community News, page 1:
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Human sciences, Linguistics, Phonetics, Phonology, Sciences A consonant sound made by a single muscle contraction, such as the sound /ɾ/ in the standard American English pronunciation of body.
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Medicine, Sciences, Surgery A piece of tissue incompletely detached from the body, as an intermediate stage of plastic surgery.
Etymology From Middle English flappen (“to flap, clap, slap, strike”), related to Dutch flappen (“to flap”), German Low German flappen (“to flap”), German flappen (“to flap”), Dutch flabberen (“to flit, flap”). Probably ultimately imitative.
Startled, the wood pigeon flew off, its wings flapping noisily.
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He could be flapping his tongue about you right this minute to anybody who'll bloody listen.2004, Robert Jordan, New Spring, page 316:
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To move loosely back and forth.
The flag flapped in the breeze.
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Ball games, Games, Hobbies, Lifestyle, Soccer, Sports For a goalkeeper to weakly attempt to play a flighted ball with the hands, failing to control it.
Former Turkey goalkeeper Rustu Recber flapped at his first Delap throw but was given a soft free-kick by referee Antony Gautier.2011 September 29, Tom Rostance, “Stoke 2 - 1 Besiktas”, in BBC Sport: