AA

AA, Aa, Double A, or Double-A may refer to:

Arts, entertainment and media

 * America's Army, a 2002 computer game published by the U.S. Army
 * Ancient Anguish, a computer game in existence since 1992
 * Aa!, a J-Pop musical group
 * Double-A (band), stylised as AA, South Korean boy band
 * Aa (album), a 2016 album by Baauer
 * AA (song), a 2021 single by Walker Hayes
 * Ace Attorney, a series of video games developed by Capcom.
 * AA Films, an Indian film distribution company
 * AA Book (disambiguation)
 * AA, the production code for the 1966 Doctor Who serial The Savages
 * Academy Award, in the film industry

Brands, organizations and enterprises

 * Alcoholics Anonymous, support organisation
 * A. A. Arms, a defunct firearms manufacturer
 * Aerolíneas Argentinas, an Argentine airline
 * Air Asia, an airline
 * Air Austral airline, former logo
 * Alcoa, a US aluminum producer, stock symbol
 * American Airlines, IATA code
 * Anadolu Agency, press agency, Turkey
 * Arakan Army, Rakhine State, Myanmar, a rebel group
 * Audio-Animatronics, used at Disney Parks
 * Academia de Artes, Mexico
 * Former US Amalgamated Association of Iron and Steel Workers
 * Architectural Association School of Architecture, London, United Kingdom
 * Astrological Association of Great Britain, London, UK
 * Auswärtiges Amt, the Foreign Office of Germany
 * Danish Association of Architects (Akademisk Arkitektforening)
 * The AA, UK motoring organization
 * AA Ireland, an Irish automotive services company
 * AA Motoring Trust, merged into IAM Motoring Trust

Philosophy and religion

 * A∴A∴, a spiritual organization created in 1907 by Aleister Crowley
 * Abhisamayalankara, or Abhisamaya-alaṅkāra, a Mahayana Buddhist text
 * Augustinians of the Assumption, a congregation of Catholic religious (priests and brothers)
 * Statue of A'a from Rurutu, a wooden fertility-god sculpture from the Pacific island of Rurutu
 * "A is A", an expression of the law of identity: each thing is identical with itself
 * Iah, an ancient moon deity
 * AA or A.A. (After Adam), year notation in the Mandaean calendar

Language

 * aa, Latin-script digraph used in the orthographies of Dutch, Finnish and other languages
 * aa, representation of letter Å in several Scandinavian languages
 * aa, a romanization of Arabic letter alif $⟨ا⟩$
 * Ꜳ, an orthographic ligature
 * Afar language (ISO 639-1 language code aa)
 * Aa (Bengali), a Bengali letter

Measurements

 * AA, a bra size
 * AA, a width in shoe sizes
 * AA battery size

Nature

 * Aa (plant), a genus of orchid
 * Aa (snail), a subgenus of snail
 * ʻAʻā or aa, a form of lava
 * A term for "river" in German hydronymy, see Aach (toponymy)

People

 * Aa (surname), a Scandinavian surname, including a list of people with this name
 * Van der Aa (surname), a Dutch surname, including a list of people with this name
 * Aa (architect), an architect in ancient Egypt
 * Anthony Armstrong (writer) (1897–1972), Anglo-Canadian writer who used the pseudonym A.A. when writing for Punch
 * Allu Arjun (born 1982), Indian actor, often abbreviated as AA in film titles

Places

 * Aa, Estonia, a village and beach in Estonia
 * Aa, Indonesia, a populated place in the South Sulawesi province of Indonesia
 * Albania, LOC MARC code
 * Ann Arbor, a city in Michigan, United States of America
 * Anne Arundel County, a county in Maryland, United States of America
 * Antarctica, WMO country code
 * Aruba, FIPS country code

Belgium

 * Aa (Nete), in the province of Antwerp, tributary of the Nete

France

 * Aa (France)

Germany

 * Aabach (Afte), formerly Große Aa, North Rhine-Westphalia
 * Aa (Möhne), North Rhine-Westphalia
 * Aa (Nethe), North Rhine-Westphalia
 * Aa (Werre), North Rhine-Westphalia
 * Bocholter Aa, North Rhine-Westphalia
 * Dreierwalder Aa, North Rhine-Westphalia
 * Kleine Aa (Aabach), a tributary of the Aabach in North Rhine-Westphalia
 * Große Aa, a tributary of the Ems in Lower Saxony
 * Große Aa (Aabach), a tributary of the Aabach in North Rhine-Westphalia
 * Münstersche Aa, North Rhine-Westphalia
 * Schaler Aa, Lower Saxony and North Rhine-Westphalia
 * Speller Aa, Lower Saxony and North Rhine-Westphalia
 * Steinfurter Aa, North Rhine-Westphalia

Netherlands

 * Aa (Meuse), North Brabant
 * Aa of Weerijs, North Brabant
 * Drentsche Aa, Drenthe and Groningen
 * Ruiten Aa, a river in Westerwolde, Groningen

Switzerland

 * Aabach (Aare), a tributary of the Aare, in Aargau canton
 * Aabach (Greifensee) or Ustermer Aa, in canton of Zürich
 * Aabach (Obersee), a tributary of Obersee (Zürichsee), in canton of St. Gallen
 * Aabach (Seetal), in the cantons of Lucerne and Aargau
 * Chli Aa (Sempachersee), a tributary of Lake Sempach in the canton of Lucerne
 * Engelberger Aa, in the cantons of Obwalden and Nidwalden
 * Gross Aa (Sempachersee), a tributary of Lake Sempach in the canton of Lucerne
 * Mönchaltorfer Aa, a tributary of Greifensee in canton of Zürich
 * Sarner Aa (river), Obwalden, tributary of Lake Lucerne

Latvia

 * Gauja, Latvia, formerly known as Livländische Aa
 * Lielupe, Latvia, formerly known as Kurländische Aa

Science and technology

 * AA amyloidosis
 * Aplastic anemia, a disease
 * Arachidonic acid, a polyunsaturated fatty acid
 * Advanced Architecture, later Amiga Advanced Graphics Architecture
 * Atlas Autocode, a computer programming language
 * AA, Audible.com file format
 * Authoritative Answer bit, in DNS, a flag for a query answer
 * AA postulate of Euclidean geometry
 * Anti-aircraft, in military use
 * Attoampere (aA), 10−18 Ampere, a unit of electric current
 * AA tree in computer science
 * Abbreviation for azidoazide azide
 * Anna's Archive, search engine of shadow libraries

Sports

 * Double-A (baseball) or Class AA, a Minor League Baseball classification level
 * American Association (1882–1891), US baseball league
 * American Association (1902–1997), US baseball league
 * American Association of Professional Baseball, North American baseball league
 * Athletics Australia
 * Amateur Athletic Union, US, since 1884

Transportation

 * AA Highway, Kentucky, US
 * Former Ann Arbor Railroad (1895–1976), Ohio and Michigan
 * Ann Arbor Railroad (1988), Ohio and Michigan
 * Former K line, New York City Subway, formerly "AA"
 * NZR AA class, a New Zealand locomotive class
 * Ascend Airways

Other uses

 * Asian Aerospace, an airshow in Asia
 * Associate of Arts, an academic degree
 * European Union Association Agreement
 * Postal abbreviation for United States armed forces in the Americas
 * Japanese internet slang for Shift JIS art
 * Internet slang for ASCII Art