Quad as a word or prefix usually means 'four'. It may refer to:

Government

Quadrilateral Security Dialogue The Quadrilateral Security Dialogue (QSD), commonly known as the Quad, is a strategic security dialogue between Australia, India, Japan and the United States that is maintained by talks between member countries. The dialogue was initiated in ...

, a strategic security dialogue between Australia, India, Japan, and the United States *

Quadrilateral group The Quadrilateral group or the Quad is an informal group which includes the trade spokespersons of Canada, the European Union, Japan, and the United States. It was first suggested at a private meeting during the 7th G7 summit in July 1981. Initial ...

, an informal group which includes the trade spokesmen of the United States, Japan, Canada, and the European Union *

Quad Cities The Quad Cities is a region of cities (originally four, see History) in the U.S. states of Iowa and Illinois: Davenport and Bettendorf in southeastern Iowa, and Rock Island, Moline and East Moline in northwestern Illinois. These cities are t ...

, a group of five cities straddling the boundary between the U.S. states of Iowa and Illinois * The "Quad", the senior members of the

Cameron–Clegg coalition The Cameron–Clegg coalition was formed by David Cameron and Nick Clegg when Cameron was invited by Queen Elizabeth II to form a new administration, following the resignation of Prime Minister Gordon Brown on 11 May 2010, after the gene ...

government in the United Kingdom from 2010 to 2015

Art and entertainment

* Matthias Quad (1557–1613), engraver and cartographer * ''Quad'' (film), 2015 * Quad (music), a musical project by Gary Ramon * ''Quad'' (play), by Samuel Beckett * ''The Quad'' (TV series), 2017 *

Quad (arts centre) Quad (branded as QUAD and also known as Derby QUAD), is an arts centre in Derby Derby ( ) is a city and unitary authority area in Derbyshire, England. It lies on the banks of the River Derwent in the south of Derbyshire, which is in the ...

, in Derby, United Kingdom *

Quad Cinema The Quad Cinema is New York City's first small four-screen multiplex theater. Located at 34 West 13th Street in Greenwich Village, it was opened by entrepreneur Maurice Kanbar, along with his younger brother Elliott S. Kanbar in October 1972. I ...

, art house in New York City, New York * Quad (company), formerly Quad/Graphics, an American printing company * Quadruple combination, the four books that comprise the canon of the LDS church

Medicine and anatomy

Quadriplegic Tetraplegia, also known as quadriplegia, is defined as the dysfunction or loss of motor and/or sensory function in the cervical area of the spinal cord. A loss of motor function can present as either weakness or paralysis leading to partial or ...

, a person paralyzed in all four limbs *

Quadriceps femoris The quadriceps femoris muscle (, also called the quadriceps extensor, quadriceps or quads) is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the sole extensor muscle of the knee, forming a large ...

, a large leg muscle group *

Quadruplets A multiple birth is the culmination of one multiple pregnancy, wherein the mother gives birth to two or more babies. A term most applicable to vertebrate species, multiple births occur in most kinds of mammals, with varying frequencies. Such bir ...

, four children from a multiple birth

Sports

Quad (figure skating) A quad, or quadruple, is a figure skating jump with at least four (but fewer than five) revolutions. All quadruple jumps have four revolutions, except for the quadruple Axel, which has four and a half revolutions. The quadruple toe loop and qu ...

, a figure skating jump with four revolutions *

Quad scull A quadruple sculling boat, often simply called a quad and abbreviated 4x, is a rowing boat used in the sport of competitive rowing. It is designed for four people who propel the boat by sculling with two oars, or "sculls", one in each hand. R ...

, a boat configuration of four rowers *

Quad skates Roller skates, are shoes or bindings that fit onto shoes that are worn to enable the wearer to roll along on wheels. The first roller skate was an inline skate design, effectively an ice skate with wheels replacing the blade. Later the "quad ska ...

, roller skates with two wheels on each of two axles * Quad, one of the divisions in

wheelchair tennis Wheelchair tennis is one of the forms of tennis adapted for wheelchair users. The size of the court, net height and rackets are the same, but there are two major differences from pedestrian tennis: athletes use specially designed wheelchairs, ...

Quadruple-double In basketball, a double-double is a single-game performance in which a player accumulates ten or more in two of the following five statistical categories: points, rebounds, assists, steals, and blocked shots. The first "double" in the term ...

, a statistical accomplishment in basketball *

Quadrennium A unit of time is any particular time interval, used as a standard way of measuring or expressing duration. The base unit of time in the International System of Units (SI) and by extension most of the Western world, is the second, defined as ab ...

, the 4-year training cycle between Olympic games

Transportation

Quad bike An all-terrain vehicle (ATV), also known as a light utility vehicle (LUV), a quad bike, or simply a quad, as defined by the American National Standards Institute (ANSI); is a vehicle that travels on low-pressure tires, with a seat that is strad ...

or all-terrain vehicle, a vehicle that travels on low-pressure tires * Quad, a

tandem bicycle A tandem bicycle or twin is a form of bicycle (occasionally a tricycle) designed to be ridden by more than one person. The term tandem refers to the seating arrangement (fore to aft, not side by side), not the number of riders. Patents relat ...

with four seats *

Quadracycle A quadracycle is a four-wheeled human-powered land vehicle. It is also referred to as a quadricycle, quadcycle, pedal car or four-wheeled bicycle amongst other terms. Quadracycles have been in use since 1853 and have grown into several fami ...

, a four-wheeled human-powered land vehicle *

Jeffery Quad The Jeffery Quad, also known as the Nash Quad or Quad is a four-wheel drive, 1-ton rated truck that was developed and built by the Thomas B. Jeffery Company from 1913 in Kenosha, Wisconsin, and after 1916 by Nash Motors, which acquired the Jeffer ...

, a four-wheel drive truck *

Quadcopter A quadcopter or quadrotor is a type of helicopter with four rotors. Although quadrotor helicopters and convertiplanes have long been flown experimentally, the configuration remained a curiosity until the arrival of the modern UAV or drone. T ...

, a four-rotor helicopter * Quad, a

chairlift An elevated passenger ropeway, or chairlift, is a type of aerial lift, which consists of a continuously circulating steel wire rope loop strung between two end terminals and usually over intermediate towers, carrying a series of chairs. Th ...

in skiing which carries four persons * Quad, or

railroad speeder A speeder (also known as a section car, railway motor car, putt-putt, track-maintenance car, crew car, jigger, trike, quad, trolley, inspection car, or a draisine) is a small railcar formerly used around the world by track inspectors and work cre ...

, a motorized vehicle used for maintenance on railroads *

Quad (rocket) In rocketry, the Armadillo Aerospace Quad vehicle called Pixel is a computer-controlled VTVL rocket that was used in 2006 to compete in the Lunar Lander Challenge. General description The quad vehicle design is a pressure fed in blow-down mode ...

, an autonomous rocket by Armadillo Aerospace

Technology

* QUAD (cipher), a stream cipher * QUaD, a microwave telescope at the South Pole * Quad antenna, a directional antenna *

Quad Electroacoustics Quad Electroacoustics is a Chinese manufacturer of hi-fi equipment, based in Shenzhen, China. Corporate history The company was founded by Peter J. Walker in 1936 in London, and was initially called ''S.P. Fidelity Sound Systems''. In 1936 ...

, a British manufacturer of audio equipment * Quadraphonic sound, four-channel sound *

Quadruplex videotape 2-inch quadruplex videotape (also called 2″ quad video tape or quadraplex) was the first practical and commercially successful analog recording video tape format. It was developed and released for the broadcast television industry in 1956 by ...

, video tape format * Quad Flat Package, a type of package for surface mounted integrated circuit * Star quad cable, four insulated conductors twisted together

Other uses

Quad (unit) A quad is a unit of energy equal to (a short-scale quadrillion) BTU, or (1.055 exajoules or EJ) in SI units. The unit is used by the U.S. Department of Energy in discussing world and national energy budgets. The global primary energy pro ...

, unit of energy, short for ''quadrillion'', 10¹⁵ BTU * Quadrangle (architecture), a space or courtyard bordered by buildings * Quad (geography), a United States Geological Survey topographical map *

Quad (typography) In typography, a quad (originally ''quadrat'') was a metal spacer used in letterpress typesetting. The term was later adopted as the generic name for two common sizes of spaces in typography, regardless of the form of typesetting used. An em quad ( ...

, a spacer used in letterpress type *

Quadrilateral In geometry a quadrilateral is a four-sided polygon, having four edges (sides) and four corners (vertices). The word is derived from the Latin words ''quadri'', a variant of four, and ''latus'', meaning "side". It is also called a tetragon, ...

, in geometry * Quad poster, a common UK size of

film poster A film poster is a poster used to promote and advertise a film primarily to persuade paying customers into a theater to see it. Studios often print several posters that vary in size and content for various domestic and international markets. Th ...

Quadrat A quadrat is a frame, traditionally square, used in ecology, geography and biology to isolate a standard unit of area for study of the distribution of an item over a large area. Modern quadrats can for example be rectangular, circular, or irregul ...

, in ecology, a small study area or a frame used to define it *

Quadrupel A Quadrupel (Flemish for 'quadruple') is a type of beer, with an alcohol by volume of 9.1% to 14.2%. There is little agreement on the status of Quadrupel as a beer style. Writer Tim Webb notes that similar beers are called '' Grand Cru'' in Be ...

, a Belgian beer * The Quad Resort and Casino, on the Las Vegas Strip *

Four-of-a-kind In poker, players form sets of five playing cards, called ''hands'', according to the rules of the game. Each hand has a rank, which is compared against the ranks of other hands participating in the showdown to decide who wins the pot. In high ...

in poker