OO

For technical reasons, "O_O" and similar titles redirect here. For the keyboard symbol, see List of emoticons.

OO or oo may refer to:

Science and technology

• ‘Ō‘ō, an extinct bird of the genus Moho
• Object-oriented programming, a computer programming paradigm
• O.O (also O.o or o.O), an emoticon to represent two eyes and a nose or mouth

Transportation

• SkyWest Airlines (IATA code: OO)
• Belgium (aircraft registration prefix: OO)
• Old Oak Common TMD, a carriage shed (Network Rail depot code: OO)

Places

• Oô, a commune in France
• Oo, Indonesia

Art and entertainment

• OO (EP), album by South Korean singer Zion.T
• OO, the production code for the 1967 Doctor Who serial The Ice Warriors

Other uses

• Oo (digraph), a digraph in orthography
• ‘O‘o stick, a traditional Hawaiian digging bar
• Original Oratory, a competitive event in high school forensic competitions
• Oakley, Inc. (NYSE stock ticker symbol: OO), subsidiary of Italian company Luxottica
• OO gauge, a 1:76.2 modelling scale in model railroading
• Official Observer, an appointed amateur radio operator

See also

• Double-O, producer and half of hip-hop duo o in the Hallo
• Infinity (∞)
• 00 (disambiguation)
• O0 (disambiguation)
• OOO (disambiguation)
• ᅇ, an obsolete unit of the Hangul alphabet