Flap may refer to:

Arts, entertainment, and media

* ''Flap'' (film), a 1970 American film * Flap, a boss character in the arcade game '' Gaiapolis'' * Flap, a minor character in the film '' Little Nemo: Adventures in Slumberland''

Biology and healthcare

* Flap (surgery), a surgical technique involving movement of vascularized tissue ** Free flap, a specific kind of surgical flap * Flapping tremor is a medical condition, also called asterixis * 5-lipoxygenase activating protein (FLAP)

Computing and networks

* The phenomenon of some variable or resource oscillating or alternating rapidly between two

states State most commonly refers to: * State (polity), a centralized political organization that regulates law and society within a territory **Sovereign state, a sovereign polity in international law, commonly referred to as a country **Nation state, a ...

Route flapping In computer networking and telecommunications Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or ...

, when a network router flips between different routes ** Link flap, errant behavior in a communications link

Engineering and design

Flap (aeronautics) A flap is a high-lift device used to reduce the stalling speed of an aircraft wing at a given weight. Flaps are usually mounted on the wing trailing edges of a fixed-wing aircraft. Flaps are used to reduce the take-off distance and the landi ...

, a lift augmentation device on an airplane wing, often near the trailing edge * Flapping, the up-and-down motion of a

helicopter rotor On a helicopter, the main rotor or rotor system is the combination of several rotary wings (rotor blades) with a control system, that generates the aerodynamic lift (force), lift force that supports the weight of the helicopter, and the thrust ...

* Flap, any hinged plate often used as a cover or a simple one-way

valve A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or Slurry, slurries) by opening, closing, or partially obstructing various passageways. Valves are technically Pip ...

** Sluice or flap gate, a pressure driven water flow control device between a channel and other water body ** Bum flap (or butt flap), a separately removable part of underwear (un)covering the buttocks ** Mudflap, a guard for tires **

Pet door A pet door or pet flap (also referred to in more specific terms, such as cat flap, cat door, kitty door, dog flap, dog door, or doggy/doggie door) is a small opening to allow pets to enter and exit a building on their own without needing a human t ...

or pet flap * Roof flap, an aerodynamic feature of race cars

Linguistics

Flap consonant In phonetics, a flap or tap is a type of consonantal sound, which is produced with a single contraction of the muscles so that one articulator (such as the tongue) is thrown against another. Contrast with stops and trills The main difference be ...

, a sound produced by brief contact between one articulator (such as the tongue) and another (such as the roof of the mouth) ** Flapping, a process by which a or a before an unstressed vowel is pronounced as a flap consonant

Other uses

* Flapping, one of the basic mechanics of

bird flight Bird flight is the primary mode of animal locomotion, locomotion used by most bird species in which birds take off and flight, fly. Flight assists birds with feeding, Sexual reproduction, breeding, avoiding predation, predators, and Bird migrati ...