| Abbreviation | Definition |
|---|---|
| ONA | Online News Association |
| ONN | Ohio News Network |
| ONQ | ON Cue |
| ONQ | WQED-TV, Pittsburgh, monthly magazine |
| OOC | Out Of Character |
| OOH | Out Of Home |
| OOH | Out of Our Heads |
| OOP | Out Of Print |
| OOPS | Object Oriented Programming System |
| OOPS | Our Outdoor Production Story |
| OOPS | Out Of Print, Sorry |
| OOR | Operation Outward Reach |
| OOTA | Online On The Air |
| OOTV | Only On TeleVision |
| OOW | Oracle OpenWorld |
| OP | Orthographic Projection |
| OP | Out of Print |
| OP | OverProof |
| OPI | Open Press Interface |
| OPL | Oilfield Publications Limited |