AR, Ar, or A&R may refer to:

Arts, entertainment, and media

Music

Periodicals

* ''

Absolute Return + Alpha ''AR: Absolute Return + Alpha'' (or ''AR'') is a hedge fund magazine founded in 2009. The magazine has its editorial offices in New York City. History and profile ''Absolute Return + Alpha'' (''AR'') was launched in September 2009, as a subsidia ...

'', a hedge fund publication *'' The Adelaide Review'', an Australian arts magazine * American Renaissance (magazine), ''American Renaissance'' (magazine), a white nationalist magazine and website * ''Architectural Review'', a British architectural journal * ''Armeerundschau'', a magazine of the East German army

Other media

* Ar, city on the fictional planet Gor * ''a.r.'' group of Polish artists and poets, including Katarzyna Kobro * Alternate reality (disambiguation), various fictional concepts

Business

* Accounts receivable, abbreviated as AR or A/R * Acoustic Research, an American audio electronics manufacturer * Aerojet Rocketdyne, an American aerospace and defense manufacturer * Aerolíneas Argentinas (IATA airline code AR) * Some Alfa Romeo car models, e.g. AR51 * Toyota AR engine

Language

* ''Ar'', the Latin letter R when spelled out * Ar (cuneiform), a cuneiform combined sign * Arabic, by ISO 639-1 language code

Mathematics, science, and technology

Computing

* ar (Unix), a Unix archive format and handling tool * Accelerated Reader, educational reading assessment software * Augmented reality, an application of virtual reality in the real world

Biology and medicine

* Androgen receptor, a nuclear hormone receptor * Aortic insufficiency, Aortic regurgitation, a heart valve disease * Autosomal recessive inheritance

Mathematics

* ar-, a prefix of inverse hyperbolic functions#Notation, inverse hyperbolic functions * Autoregressive model, concerning random processes in statistics

Physics and chemistry

* Aqua regia, a chemical mixture * Archimedes number in fluid dynamics * Argon, symbol Ar, a chemical element * Aryl group in organic chemistry * Relative atomic mass, symbolized as ''A''_r

Other uses in science and technology

* Anti-reflective, coating of lenses * Aspect ratio (aeronautics), of a wing

Military and weapons

* US Navy hull classification symbol for repair ships * Armalite Rifle ** AR-15 style rifle, rifles based on ArmaLite's AR-15 * Army Reserve (Ireland), the land component of the Irish Reserve Defence Forces (RDF)

Places

* Ar (city), in ancient Moab * Appenzell Ausserrhoden, Switzerland * Province of Arezzo, Italy, vehicle registration code * Argentina (ISO 3166-1 alpha-2 country code) ** .ar, the country code Top Level Domain for Argentina * Arkansas, United States * Armstrong–Ringsted Community School District, Iowa, United States

Politics and ethics

* Affirmative Repositioning, a political movement in Namibia * Animal rights, a philosophy * Animal rights movement, a social movement advocating for other animals * Antipodean Resistance, an Australian neo-Nazi group

Other uses

* 🜇 or AR, a List of numismatic abbreviations, numismatic abbreviation for "silver" * Argent, the heraldic tincture of silver * Assistant referee (association football) * Auto rickshaw, a motorized three-wheeled vehicle common in South Asia * Avis de réception, postal advice or acknowledgement of receipt {{Disambiguation