- One who operates.
- A telecommunications facilitator whose job is to establish temporary network connections.
- (mathematics) A function or other mapping that carries variables defined on a domain into another variable or set of variables in a defined range.
- Another name for Chinese whispers.
- (informal) A person who is adept at making deals or getting results, especially one who uses questionable methods.
- A member of a military Special Operations unit.
- Occupational Therapist/Therapy
- (biblical) Old Testament
- (computing) Off-Topic
- Offensive Tackle, American & Canadian Football