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
Rivers
Belgium
- Aa (Nete), in the province of Antwerp, tributary of the Nete
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
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