OO

OO or oo may refer to:

• Oô, a commune in France
• ‘Ō‘ō, an extinct bird of the genus Moho
• OO, Belgium's ICAO aircraft registration prefix
• O.O (also O.o or o.O), an emoticon to represent two eyes and a nose or mouth
• Oo (digraph), a digraph in orthography
• OO gauge, a 1:76.2 modelling scale in model railroading
• Oakley, Inc., NYSE stock ticker symbol OO
• Object-oriented programming, a computer programming paradigm
• Official Observer, an appointed amateur radio operator
• The carriage shed at Old Oak Common TMD (Network Rail depot code OO)
• Original Oratory, a competitive event in high school forensic competitions
• SkyWest Airlines (IATA code OO)

See also

• 00 (disambiguation)
• O0 (disambiguation)
• Double-O, a producer and half of hip-hop duo Kidz in the Hall
• OOO (disambiguation)
• ∞, a symbol used to indicate infinity
• ᅇ, an obsolete unit of the Hangul alphabet