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

Arts, entertainment, and media

Music

Artists and repertoire Artists and repertoire (or A&R for short) is the division of a record label or music publishing company that is responsible for scouting, financing, and overseeing the artistic development of recording artists and songwriters. It also acts as a l ...

* ''AR'' (EP), the debut EP by Addison Rae

Periodicals

* '' Absolute Return + Alpha'', a hedge fund publication *''

The Adelaide Review ''The Adelaide Review'' (AR) was a monthly print arts magazine and dynamic website in Adelaide, South Australia. It was first published in 1984, but gained standing after one of its writers, Christopher Pearson, took it over in 1985. In March ...

'', an Australian arts magazine * ''American Renaissance'' (magazine), a white nationalist magazine and website * ''

Architectural Review ''The Architectural Review'' is a monthly international architectural magazine. It has been published in London since 1896. Its articles cover the built environment – which includes landscape, building design, interior design and urbanism � ...

'', 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 * Alternate reality (disambiguation), various fictional concepts

Business

Accounts receivable Accounts receivable, abbreviated as AR or A/R, are legally enforceable claims for payment held by a business for goods supplied or services rendered that customers have ordered but not paid for. The accounts receivable process involves customer on ...

, abbreviated as AR or A/R *

Acoustic Research Acoustic Research was a Cambridge, Massachusetts-based company that manufactured high-end audio equipment. The brand is now owned by VOXX. Acoustic Research was known for the AR-3 series of speaker systems, which used the acoustic suspension wo ...

, an American audio electronics manufacturer *

Aerojet Rocketdyne Aerojet Rocketdyne is a subsidiary of American Arms industry, defense company L3Harris that manufactures rocket, Hypersonic flight, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Aerojet traces ...

, an American aerospace and defense manufacturer * Aerolíneas Argentinas (IATA airline code AR) * AtkinsRéalis, Canadian engineering company * Some

Alfa Romeo Alfa Romeo Automobiles S.p.A. () is an Italian carmaker known for its sports-oriented vehicles, strong auto racing heritage, and iconic design. Headquartered in Turin, Italy, it is a subsidiary of Stellantis Europe and one of 14 brands of mu ...

car models, e.g. AR51 *

Toyota AR engine The AR engine family is an Inline-4 piston engine series by Toyota, first introduced in 2008 for the RAV4, and subsequently for the Highlander, Venza, Camry and Scion tC. The AR series uses a die-cast aluminium engine block and aluminium ...

Language

* ''Ar'', the Latin letter R when spelled out * Ar (cuneiform), a cuneiform combined sign *

Arabic Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasiatic languages, Afroasiatic language family spoken primarily in the Arab world. The International Organization for Standardization (ISO) assigns lang ...

, by ISO 639-1 language code

Science and technology

Computing

Accelerated Reader Accelerated Reader (AR) is an educational program created by Renaissance Learning. It is designed to monitor and manage students' independent reading practice and comprehension in both English and Spanish. The program assesses students' perfor ...

, educational reading assessment software * Adaptive routing, in networking * Adobe Aero, an Adobe software *

ar (Unix) ar, short for archiver, is a shell command for maintaining multiple files as a single archive file. Originally developed for Unix, it is widely available on Unix-based systems, and similar commands are available on other platforms. Today, ar ...

, a Unix archive format and handling tool *

Augmented reality Augmented reality (AR), also known as mixed reality (MR), is a technology that overlays real-time 3D computer graphics, 3D-rendered computer graphics onto a portion of the real world through a display, such as a handheld device or head-mounted ...

, an application of virtual reality in the real world

Biology and medicine

Androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in th ...

, a nuclear hormone receptor *

Aortic regurgitation Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. As a conse ...

, a heart valve disease *

Autosomal recessive inheritance In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the Phenotype, effect of a different variant of the same gene on Homologous chromosome, the other copy of the chromosome. The firs ...

Mathematics

* ar-, a prefix of

inverse hyperbolic functions In mathematics, the inverse hyperbolic functions are inverses of the hyperbolic functions, analogous to the inverse circular functions. There are six in common use: inverse hyperbolic sine, inverse hyperbolic cosine, inverse hyperbolic tangen ...

Autoregressive model In statistics, econometrics, and signal processing, an autoregressive (AR) model is a representation of a type of random process; as such, it can be used to describe certain time-varying processes in nature, economics, behavior, etc. The autoregre ...

, concerning random processes in statistics

Physics, chemistry and engineering

Anti-reflective An antireflective, antiglare or anti-reflection (AR) coating is a type of optical coating applied to the surface of lenses, other optical elements, and photovoltaic cells to reduce reflection. In typical imaging systems, this improves the effi ...

, coating of lenses *

Aqua regia Aqua regia (; from Latin, "regal water" or "royal water") is a mixture of nitric acid and hydrochloric acid, optimally in a molar concentration, molar ratio of 1:3. Aqua regia is a fuming liquid. Freshly prepared aqua regia is colorless, but i ...

, a chemical mixture *

Archimedes number In viscous fluid dynamics, the Archimedes number (Ar), is a dimensionless number used to determine the motion of fluids due to density differences, named after the ancient Greek scientist and mathematician Archimedes. It is the ratio of gravita ...

in fluid dynamics *

Argon Argon is a chemical element; it has symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most abundant gas in Earth's atmosphere, at 0.934% (9340 ppmv). It is more than twice as abu ...

(Ar), a chemical element * Aryl group, in organic chemistry *

Aspect ratio (aeronautics) In aeronautics, the aspect ratio of a wing is the ratio of its span to its mean chord. It is equal to the square of the wingspan divided by the wing area. Thus, a long, narrow wing has a high aspect ratio, whereas a short, wide wing has a low a ...

, of a wing *

Relative atomic mass Relative atomic mass (symbol: ''A''; sometimes abbreviated RAM or r.a.m.), also known by the deprecated synonym atomic weight, is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a gi ...

(''A''_r), the ratio of the average mass of atoms of an element

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 Army Reserve (AR) () is the reserve land component of the Defence Forces (Ireland), Irish Defence Forces. It is the second line reserve of the Irish Army. The Army Reserve involves active military service on a part-time basis, and is one of t ...

, the land component of the Irish Reserve Defence Forces (RDF)

Places

* Ar (city), in ancient Moab *

Appenzell Ausserrhoden Canton of Appenzell Ausserrhoden ( ; ; ; ), in English sometimes Appenzell Outer Rhodes, is one of the Canton of Switzerland, 26 cantons forming the Switzerland, Swiss Confederation. It is composed of twenty municipalities. The seat of the gove ...

, Switzerland *

Province of Arezzo The province of Arezzo () is a province in the Tuscany region of Italy. Its capital is the city of Arezzo. The province is bordered by the regions of Marche, Emilia-Romagna, Umbria, and the provinces Siena and Florence of Tuscany. It has an area ...

, Italy, vehicle registration code *

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

(ISO 3166-1 alpha-2 country code) ** .ar, the country code Top Level Domain for Argentina *

Arkansas Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...

, United States * Armstrong–Ringsted Community School District, Iowa, United States *

Arunachal Pradesh Arunachal Pradesh (; ) is a States and union territories of India, state in northeast India. It was formed from the North-East Frontier Agency (NEFA) region, and India declared it as a state on 20 February 1987. Itanagar is its capital and la ...

, a state of India

Politics and ethics

* Affirmative Repositioning, a political movement in Namibia *

Animal rights Animal rights is the philosophy according to which many or all Animal consciousness, sentient animals have Moral patienthood, moral worth independent of their Utilitarianism, utility to humans, and that their most basic interests—such as ...

, a philosophy *

Animal rights movement The animal rights movement, sometimes called the animal liberation, animal personhood, or animal advocacy movement, is a social movement that advocates an end to the rigid moral and legal distinction drawn between human and non-human animals, ...

, a social movement advocating for other animals * Antipodean Resistance, an Australian neo-Nazi group

Other uses

* 🜇 or AR, a numismatic abbreviation for "silver" *

Argent In heraldry, argent () is the tincture of silver, and belongs to the class of light tinctures called "metals". It is very frequently depicted as white and usually considered interchangeable with it. In engravings and line drawings, regions to b ...

, the heraldic tincture of silver *

Assistant referee (association football) In association football, an assistant referee (also known as a linesman) is an official who assists the referee in administering the Laws of the Game during a match. Although assistants are not required under the Laws, at most organised levels ...

Auto rickshaw An auto rickshaw is a motorized version of the pulled rickshaw or cycle rickshaw. Most have three wheels and do not tilt. They are known by many other terms in various countries, including three-wheeler, Adaidaita Sahu, Keke-napep, Maruwa, auto, ...

, a motorized three-wheeled vehicle common in South Asia * Avis de réception, postal advice or acknowledgement of receipt {{Disambiguation