OP

OP, O.P., Op, or Op. may refer to:

Arts

• Opus number, used to denote one work of musical composition from many
• Out of print, a status of a book title at a publishing house
• Opposite prompt, a stage right prompt corner on a theatre stage

Internet and gaming

• Original post or original poster, the first post in or person initiating a new Internet thread
• Internet Relay Chat operator
• Overpowered, in video games when a particular aspect or character is lacking game balance

Mathematics

• Op (statistics), a symbol used in probability mathematics
• Operator (mathematics), a mapping from one vector space or module to another
• Octagonal prism, a prism formed by square sides and two regular octagon caps

Organizations

• Dominican Order (Latin: Ordo Praedicatorum), a catholic religious order
• Ocean Pacific, a retail clothing company based in California, USA
• Oborový podnik ("specialized business"), a bygone Czechoslovakian state designation for a business entity
• OP Financial Group, Finnish financial services company

Education

• Oratory Preparatory School, a Catholic preparatory day school for boys in New Jersey, United States
• Overall Position, the grade appointed to Queensland high-school graduates
• Old Pauline, an ex-pupil of St Paul's School, London; see List of Old Paulines

Other

• Opening alias Introduction
• Orange pekoe, a grade of black teas
• Organophosphate, the general name for esters of phosphoric acid
• Surgical operation
• One Piece, a Japanese manga and anime
• Optimus Prime, a Transformer from the films/comics: Transformers

See also

• Op-amp, short for Operational amplifier
• Op-ed, a newspaper opinion piece of a writer unaffiliated with the editorial board
• Operation (disambiguation)
• Operator (disambiguation)
• OPS (disambiguation)
• Op. cit., opere citato, or "in the work cited"
• 0P (disambiguation)