AO

AO may refer to:

cience and technology

* .ao, the top-level Internet domain for Angola
* Adaptive optics, a technology used in astronomical telescopes
* Arbeitsgemeinschaft für Osteosynthesefragen, a nonprofit organization dedicated to musculoskeletal injuries
* Arctic oscillation, a climate pattern
* The AMSAT-OSCAR satellite naming convention
* The atomic form of oxygen

Media and entertainment

* AO Recordings, a record label
* Anarchy Online, a science fiction online role-playing game
* Lord Ao, a fictional deity in the "Dungeons & Dragons" universe
* Adults Only, a video game rating

Athletes

* Aaron Owens, an American streetball player
* Alexander Ovechkin, a Russian hockey player in the American National Hockey League

Other meanings

* Ao (color), a Japanese word meaning both 'blue' and 'green'
* Ao (mythology), a deity in Māori mythology
* Ao people, a Naga people of northeast India
* Ao language, the language of the Ao people
* Angola, a country, AO in 2-letter ISO code and NATO country code
* Australian Airlines, AO in IATA code
* The Alice Ottley School, in Worcester, England
* Administrative Office of the United States Courts
* A United States Navy hull classification symbol
* An officer of the Order of Australia
* A kind of wood carving by the people of Easter Island

ee also

* A0 ("A-zero")
* Todd-AO