flap

American  

[flap] / flæp /

verb (used without object)

• flaps,
  present (3rd person singular)
• flapped,
  past participle,  past
• flapping
  present participle

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.

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verb (used with object)

• flaps,
  present (3rd person singular)
• flapped,
  past participle,  past
• flapping
  present participle

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

• flaps
  plural

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.

flap British  

/ flæp /

verb

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 down

   the curtains flapped in the breeze

3. informal (intr) to become agitated or flustered; panic

4. to deal (a person or thing) a blow with a broad flexible object

5. 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

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noun

1. the action, motion, or noise made by flapping

   with 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

Other Word Forms

Derived Forms

• flapless
  adjective
• unflapping
  adjective

Inflected Forms

Nouns

• flaps
  plural

Participles

• flapping
  present
• flapped
  past

Conjugated Forms

Present

• flap
  simple
• flaps
  simple
• have flapped
  perfect
• has flapped
  perfect
• am flapping
  progressive
• are flapping
  progressive
• is flapping
  progressive
• have been flapping
  perfect progressive
• has been flapping
  perfect progressive

Past

• flapped
  simple
• had flapped
  perfect
• was flapping
  progressive
• were flapping
  progressive
• had been flapping
  perfect progressive

Future

• will flap
  simple
• will have flapped
  perfect
• will be flapping
  progressive
• will have been flapping
  perfect progressive

Etymology

Origin of flap

First recorded in 1275–1325; Middle English flappe “a blow, slap,” flappen “to hit, slap”; compare Dutch flap, flappen

Explanation

You're probably familiar with the verb to "flap," which is what birds do with their wings. But as a noun, a flap is a fuss, an argument, or a gossipy feud. A big part of the pleasure of reality TV shows is watching how quickly a person can start a flap. A dumb remark, a furtive glance, a missed phone call: any of these things can start the characters bickering. And the flap can go on for an entire season! One way to remember the meaning of the verb to flap is to imagine the sound of many wings flapping. That's the sound a flap might make if you could hear it. The leak from the senator's press agent might have caused a firestorm. Instead it resulted in just a minor flap.

Example Sentences

See Examples For:

flap flaps flapped flapping

That’s clearly targeting a customer who is now priced out of flap bags selling for $10,000 and up.

From The Wall Street Journal ● Sep. 24, 2026

Why are people in such a flap about pigeons?

From BBC ● Sep. 12, 2026

He explained the idea came when they had to move their cat flap and "it went to the corner of the house... which meant that he came into the house via a cupboard".

From BBC ● Sep. 4, 2026

Some beachgoers say that when they flap in the wind, Shibumis are so loud that it’s hard to hold a conversation under or even near one.

From The Wall Street Journal ● May 23, 2026

“To accelerate, simply flap your arms faster. However, be advised: The faster you fly, the more energy your pterodactyl will consume. Your winged avatar will have a ‘life battery’ icon glowing on its back.

From "Mr. Lemoncello's Library Olympics" by Chris Grabenstein

They spoke to each other through the meal flaps in their doors on the high security unit.

From BBC ● Sep. 26, 2026

As the valve tissue degenerates, the thin flaps that should meet neatly can thicken, stretch, or lose their normal shape.

From Science Daily ● Jul. 12, 2026

An old Catalan independence flag hanging by its entrance flaps in the wind, and the sound of pigs grunting and squealing in the farm buildings can be heard in the distance.

From BBC ● Apr. 5, 2026

These thrust differentials are coordinated with dual flaps on the trailing edges of the stubby wings.

From The Wall Street Journal ● Oct. 17, 2025

I cleaned the tires, polished up the front bumper, practically licked the mud flaps clean.

From "Anthem of a Reluctant Prophet" by Joanne Proulx

A string of miniature national flags flapped in the wind.

From The Wall Street Journal ● Aug. 1, 2026

Thai flags flapped in the breeze and barbed wire lay scattered in Klong Paeng, another border village on the Thai military trip.

From Barron's ● Feb. 7, 2026

The much criticised Youssef Chermiti scored an extraordinary double before Kasper Schmeichel flapped at Mikey Moore's perfunctory shot.

From BBC ● Jan. 5, 2026

A U.S. flag flapped on a pole just above a Hanwha company flag.

From The Wall Street Journal ● Nov. 10, 2025

Preparing for their journey south, the martins flapped and fretted in the eaves, and, from the blanket of mist hovering over the lake, I heard the harsh, lonely cry of the mallards.

From "The Secret History" by Donna Tartt

SHANGRI-LA, China—When China’s masses want to experience the Tibet of chanting, crimson-robed monks and prayer flags flapping in the wind, they don’t go to Tibet.

From The Wall Street Journal ● Oct. 5, 2026

This newer design has larger flapping wings that support more agile flight.

From Science Daily ● Sep. 22, 2026

The speed of my spinning nunchucks wasn’t nearly as fearsome as the flapping of my upper arm flab.

From Los Angeles Times ● Sep. 11, 2026

Floridians are flapping over what should be the state bird.

From MarketWatch ● Jun. 24, 2026

Clare leapt every few strides, practically flying through the air, his cape flapping behind him heroically.

From "The Undead Fox of Deadwood Forest" by Aubrey Hartman

Related Words

• dangle
• flail
• flop
• hang
• thrash
• vibrate