AR, Ar, or A&R may refer to:
Arts, entertainment, and media
Music Artists and repertoire AR (EP), the debut EP by Addison Rae
Periodicals Absolute Return + Alpha, a hedge fund publication The Adelaide Review, an Australian arts 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, an avant-garde art group
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) AtkinsRéalis, Canadian engineering company 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
Science and technology Computing Accelerated Reader, educational reading assessment software Adaptive routing, in networking Adobe Aero, an Adobe software ar (Unix), a Unix archive format and handling tool Augmented reality, a type of 3D human-computer interaction similar to virtual reality
Biology and medicine Androgen receptor, a nuclear hormone receptor Antimicrobial resistance to drugs Aortic regurgitation, a heart valve disease Autosomal recessive inheritance
Mathematics ar-, a prefix of inverse hyperbolic functions Autoregressive model, concerning random processes in statistics
Physics, chemistry and engineering Aqua regia, a chemical mixture Archimedes number in fluid dynamics Argon (Ar), a chemical element Aryl group, in organic chemistry Aspect ratio (aeronautics), of a wing Relative atomic mass (Ar), the ratio of the average mass of atoms of an element Anti-reflective coating
Military and weapons A US Navy hull classification symbol: Repair ship (AR) 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 Arunachal Pradesh, a state of India
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 Alternate reality (disambiguation), includes various concepts 🜇 or AR, a 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
See also ARTV (disambiguation)