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) Flap surgery is a technique in plastic and reconstructive surgery where any type of tissue is lifted from a donor site and moved to a recipient site with an intact blood supply. This is distinct from a graft, which does not have an intact blo ...

, a surgical technique involving movement of vascularized tissue ** Free flap, a specific kind of surgical flap * 5-lipoxygenase activating protein (FLAP)

Computing and networks

* The phenomenon of some variable or resource

oscillating Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples of oscillation include a swinging pendulum ...

or alternating rapidly between two states **

Route flapping In computer networking and telecommunications, route flapping occurs when a router alternately advertises a destination network via one route then another, or as unavailable and then available again, in quick sequence. Route flapping is caused b ...

, when a network router flips between different routes **

Link flap Link flap is a condition where a communications link alternates between ''up'' and ''down'' states. Link flap can be caused by end station reboots, power-saving features, incorrect duplex configuration or marginal connections and signal integrity ...

, 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 landin ...

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

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

* 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 slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fitting ...

Sluice Sluice ( ) is a word for a channel controlled at its head by a movable gate which is called a sluice gate. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway and can be considered ...

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 mudflap or mud guard is used in combination with the vehicle fender to protect the vehicle, passengers, other vehicles, and pedestrians from mud and other flying debris thrown into the air by the rotating tire. A mudflap is typically made fr ...

, 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 ...

or pet flap *

Roof flap A roof flap is an aerodynamic feature on race cars, mainly stock cars, which functions as an emergency spoiler to prevent the vehicle from lifting off the ground. The flaps are stowed during normal vehicle operation; however, in certain situatio ...

, 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 bet ...

, a sound produced by brief contact between one articulator (such as the tongue) and another (such as the roof of the mouth) **

Flapping Flapping or tapping, also known as alveolar flapping, intervocalic flapping, or ''t''-voicing, is a phonological process found in many varieties of English, especially North American, Cardiff, Ulster, Australian and New Zealand English, whereb ...

, 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 locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding predators, and migrating. Bird flight is one of the most complex forms of locomo ...