| Abbreviation | Definition |
|---|---|
| OPM | Official Playstation Magazines |
| OPM | One Punch Man |
| OPM | Over Priced Magazine |
| OPRA | Online Press Release Archive |
| OPV | Other People's Views |
| ORB | Opinion Research Business |
| ORC | Opinion Reference Comment |
| ORCA | Only Rendered Creations Accepted |
| ORF | Österreichischer RundFunk (Austrian Broadcasting) |
| ORIG | Original |
| ORO | Ontario Reid Omnibus Poll |
| ORR | Oriental Rug Review |
| ORT | Owned Reference To |
| ORTF | Office de Radiodiffusion Television Francaise |
| ORTF | Organisation Radiodiffusion Télévision Française |
| OS | Off Screen |
| OS | Old Style |
| OSC | Open Sound Control |
| OSD | Order for Snapes Defence |
| OSD | Original Story Debate |