AO, aO, Ao, or ao may refer to:

Places

Ao (building) Ao Building is a commercial building located in Kita-Aoyama 3-chome, Minato-ku, Tokyo. AO Building was designed by Nihon Sekkei, which also designed Ghibli Museum and Toranomon Hills. The 16-story reinforced concrete building is asymmetrical ...

Ao, Estonia Ao is a village in Väike-Maarja Parish, Lääne-Viru County, in northeastern Estonia Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to t ...

, village in Väike-Maarja Parish, Lääne-Viru County, Estonia *

Ao Line The is a commuter railway line in Hyōgo Prefecture, Japan, operated by the Kobe Electric Railway (Shintetsu). It connects Kobe with its northwestern suburb, Ono, Hyogo, Ono. The line is long, extending from Suzurandai Station, Suzurandai in K ...

, commuter railway line in Hyōgo Prefecture, Japan * Ao River (Fujian), in China * Ao Station, railway station in the city of Ono, Hyōgo Prefecture, Japan *

Aodu Zhengzhou is the capital of Henan, China. Located in northern Henan, it is one of the nine national central cities in China, and serves as the political, economic, technological, and educational center of the province. The Zhengzhou metropolit ...

, capital of Shang dynasty, near Zhengzhou *

Aoshima, Ehime , also known as , is an island in Ehime Prefecture, Japan, known for its large number of feline residents and small number of people. Felines have been reported by news outlets to outnumber humans by ratios between 6:1 and 10:1, but as elderly ...

, island in Japan *

Aoshima, Miyazaki is an islands of Japan, island located in Miyazaki, Miyazaki, Miyazaki, Miyazaki Prefecture, Japan. The island has a surface area of and a height of . The island is part of the Aoshima Shrine. Miyazaki′s Aoshima neigbbourhood consists of the ...

, island in Japan *

Angola Angola, officially the Republic of Angola, is a country on the west-Central Africa, central coast of Southern Africa. It is the second-largest Portuguese-speaking world, Portuguese-speaking (Lusophone) country in both total area and List of c ...

(ISO 3166-1 alpha-2 code AO)

Arts and entertainment

* Adults Only, an entertainment rating * AO Music (AOmusic), a world-music fusion group consisting of Jay Oliver,

Miriam Stockley Miriam Arlene Stockley (born 15 April 1962) is a South African singer. She was born in Johannesburg, and her work is influenced by the Music of Africa, African music of her home country. Her distinctive ''vocal warm up#Vocalise, vocalise'' style ...

and others * Ao: The Last Hunter, a 2010 prehistoric drama movie * '' Eureka Seven: AO'', Japanese mecha anime television series *

Lord Ao ''Forgotten Realms'' is a campaign setting for the ''Dungeons & Dragons'' (''D&D'') fantasy role-playing game. Commonly referred to by players and game designers as "The Realms", it was created by game designer Ed Greenwood around 1967 as a setti ...

, a fictional deity in the ''Dungeons & Dragons'' universe *

Annoying Orange ''Annoying Orange'' is an American comedy web series created by Dane Boedigheimer (known online as DaneBoe). Set in a world of anthropomorphic food, the series follows its titular protagonist, Orange, who always annoys others by telling c ...

, an American comedy web series

Businesses and organizations

* AO (originally American Optical Company) eyeglass lenses, a brand now merged with Carl Zeiss Vision *

AO Foundation The AO Foundation is a nonprofit organization dedicated to improving the care of patients with musculoskeletal injuries or pathologies and their sequelae through research, development, and education of surgeons and operating room personnel. The AO ...

(originally ), a non-profit organisation dedicated to the treatment of trauma and disorders of the musculoskeletal system *

AO Racing Autumn Oaks Racing, doing business as AO Racing, is an American sports car racing team that currently competes in the LMP2 and the GTD Pro classes of the IMSA SportsCar Championship and in LMP2 in the European Le Mans Series. The team was found ...

, an American sports car racing team *

AO World AO World plc, trading as ao.com, is an electrical retailer based in Bolton, England. It operates in the United Kingdom (ao.com), and previously operated in Germany (ao.de) and the Netherlands (ao.nl), specialising in household appliances and ele ...

, a UK retailer of household appliances trading under the brand name ao.com * AO, or (), a type of Russian corporate entity; see

open joint-stock company A public joint-stock company, abbreviated PJSC (, abbreviated ) or open joint-stock company, abbreviated OJSC (, abbreviated ), is a type of company in many successor states of the Soviet Union, particularly in Russia. Its distinguishing featur ...

Athletics Ontario Athletics Ontario is the governing body of track and field sports in Ontario, Canada. Athletics Ontario was founded in 1974 under the name Ontario Track and Field Association to replace several regional bodies under Athletics Canada. In 2008 its n ...

, formally Ontario Track and Field Association (OTAF) *

Australian Airlines Australian Airlines was a full-service airline based in Australia, serving Australian and Asian destinations between 2002 and 2006. It was an all-economy, full-service international leisure carrier, and was a wholly owned subsidiary of Qant ...

(IATA code AO)

Government and politics

Administrative Office of the United States Courts Administration may refer to: Management of organizations * Management, the act of directing people towards accomplishing a goal: the process of dealing with or controlling things or people. ** Administrative assistant, traditionally known as a s ...

Administrative Officer (United Kingdom) In the United Kingdom, the Civil Service is the permanent bureaucracy or secretariat of Crown employees that supports His Majesty's Government, the Scottish Government and the Welsh Government, which is led by a cabinet of ministers chosen ...

, a grade within the United Kingdom's Civil Service *

Administrative Officer (Hong Kong) The Administrative Officer (AO) ( zh, 政務主任) is a high-ranking civil service grade in the Government of Hong Kong. The AOs are cadres of multi-skilled professional administrators who play key roles in the government agencies. The AOs are po ...

, a grade within the Hong Kong's Civil Service *

Autonomous oblast An autonomous oblast is an autonomous entity within the state which is on the ''oblast'' (province) level of the overall administrative subdivision. There were autonomous oblasts of the Soviet Union and later some federal subjects of Russia w ...

, type of Russian administrative division *

Autonomous okrug Autonomous okrugs, () which are also referred to as "autonomous districts" or "autonomous areas" are a type of federal subjects of Russia, federal subject of the Russia, Russian Federation and simultaneously an administrative division type of ...

, type of Russian administrative division * NSDAP/AO, Foreign Organization branch of the Nazi Party *

Officer of the Order of Australia The Order of Australia is an Australian honours and awards system, Australian honour that recognises Australian citizens and other persons for outstanding achievement and service. It was established on 14 February 1975 by Elizabeth II, Monarch ...

, postnominal AO

Military

Area of operations In U.S. armed forces parlance, an area of operations (AO) is an operational area defined by the force commander for land, air, and naval forces' conduct of combat and non-combat activities. Areas of operations do not typically encompass the entire ...

, a U.S. military term * A US Navy hull classification symbol: Fleet oiler (AO) * AO-, the prefix for several firearms *

Aviation Ordnanceman Aviation Ordnanceman (abbreviated as AO) is a United States Navy Naval Job. History Aviation Ordnancemen operate and handle aviation ordnance equipment. They are responsible for the maintenance of Gun, guns, Bomb, bombs, Torpedo, torpedoes, R ...

, a United States Navy occupational rating

Philosophy and religion

* Alpha and Omega (abbreviation) * Ao (Māori mythology), a deity in Māori mythology *

Ao (turtle) Ao ( <

Old Chinese

(

, a creature in Chinese mythology * Ao, a type of Easter Island wood carving

Science and technology

* (697402) Ao, a main-belt asteroid * .ao, top-level Internet domain code for Angola *

Adaptive optics Adaptive optics (AO) is a technique of precisely deforming a mirror in order to compensate for light distortion. It is used in Astronomy, astronomical telescopes and laser communication systems to remove the effects of Astronomical seeing, atmo ...

, an astronomical imaging technology *

Ambient occlusion In 3D computer graphics, modeling, and animation, ambient occlusion is a shading and rendering technique used to calculate how exposed each point in a scene is to ambient lighting. For example, the interior of a tube is typically more occlude ...

, a shading method in computer graphics * AMSAT-OSCAR, a satellite naming convention *

Applied Optics ''Applied Optics'' is a peer-reviewed scientific journal published by Optica three times a month. It was established in 1962 with John N. Howard as founding editor-in-chief and Patricia Wakeling as managing editor. Wakeling worked on the journal ...

, scientific journal published by the Optical Society of America (OSA) *

Arctic oscillation The Arctic oscillation (AO) or Northern Annular Mode/Northern Hemisphere Annular Mode (NAM) is a weather phenomenon at the Arctic pole north of 55 degrees latitude. It is an important mode of climate variability for the Northern Hemisphere. The s ...

, a climate pattern *

Atomic orbital In quantum mechanics, an atomic orbital () is a Function (mathematics), function describing the location and Matter wave, wave-like behavior of an electron in an atom. This function describes an electron's Charge density, charge distribution a ...

, in physics and chemistry * Ao, the

atomic symbol Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist ...

for the misidentified

chemical element A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its ...

Ausenium ''Ausenium'' (atomic symbol Ao) and ''Hesperium'' (atomic symbol Es) were the names initially assigned to the transuranic elements with atomic numbers 93 and 94, respectively. The discovery of the elements, now discredited, was made by Enrico Fermi ...

. *

Acridine orange Acridine orange is an organic compound that serves as a nucleic acid-selective fluorescent dye with cationic properties useful for cell cycle determination. Acridine orange is cell-permeable, which allows it to interact with DNA by intercalation ...

, a fluorescent dye *

Authorship obfuscation Adversarial stylometry is the practice of altering writing style to reduce the potential for stylometry to discover the author's identity or their characteristics. This task is also known as authorship obfuscation or authorship anonymisation. St ...

, a privacy technique

Surnames and initials

Ao (surname) Áo is Mandarin pinyin and Wade–Giles romanization of the Chinese surname written in Chinese character. It is romanized as Ngo in Cantonese. Ao is listed 375th in the Song dynasty classic text ''Hundred Family Surnames''. As of 2008, it is the ...

(), a Chinese surname *

Ou (surname) Ou is the pinyin romanization of the Chinese surnames and , which share a common origin with the compound surname Ouyang (), from the ruling family of the State of Yue during the Spring and Autumn period. They are commonly romanized as Au or ...

(/ and /), romanized as Ao in Cantonese *

Ao Omae is a Japanese fiction writer. Born in Hyōgo Prefecture, he lived in Kyoto until 2022, when he relocated to Tokyo. Writing career Omae made his debut in 2016 with the short story "Kanojo wo basutabu ni irete moyasu" (彼女をバスタブにい ...

(大前粟生, Ōmae Ao, born 1992), Japanese fiction writer *

Aaron Owens Aaron Owens (born March 20, 1974), better known by his nickname "AO", is an American streetball player from North Philadelphia. In 2013, Owens participated in the Ball4Real World Tour. He was on the AND1 Mixtape Tour from its creation until 20 ...

(born 1976), American streetball player

Other uses

* Alphabetically ordered * Ao (color) * Ao (digraph) *

Ao languages The Ao or Central Naga languages are a small family of Sino-Tibetan languages spoken by various Naga peoples of Nagaland in northeast India India, officially the Republic of India, is a country in South Asia. It is the List of cou ...

Ao Naga The Aos are a major Naga ethnic group native to Mokokchung District of Nagaland in Northeast India. Their main territory is from Tsüla (Dikhu) Valley in the east to Tsürang (Disai) Valley in the west in Mokokchung District. The Ao Nagas r ...

, an Indian ethnic group * or , meaning extraordinary professor ( academic rank in Germany) *

Australian Open The Australian Open (stylized ΛO) is a tennis tournament organised by Tennis Australia annually at Melbourne Park in Melbourne, Victoria (state), Victoria, Australia. It is chronologically the first of the four Grand Slam (tennis), Grand Sl ...

, an annual tennis tournament in Melbourne, Australia * A, an abbreviation of "Anno", meaning "In the year" (as in

Anno Domini The terms (AD) and before Christ (BC) are used when designating years in the Gregorian calendar, Gregorian and Julian calendar, Julian calendars. The term is Medieval Latin and means "in the year of the Lord" but is often presented using "o ...

) * Te Ao Māori (literally "The Māori world"), Māori cultures and traditions