| Abbreviation | Definition |
|---|---|
| OSJ | Orchestra of St John |
| OSJ | Orchestra of St John's |
| OSQ | Oak Street Quartet |
| OSQ | Original Sax Quartet |
| OSS | Old School Saturday |
| OSS | Open Sound System |
| OST | Official Sound Track |
| OSZ | OneSideZero |
| OT | Old Time |
| OT | Out of Tune |
| OTAF | Of Thieves and Fiends |
| OTB | Off The Beat |
| OTBC | Old Town Blues Club |
| OTDE | Off The Deep End |
| OTL | Only The Lonely |
| OTO | Overture To Orchestra |
| OTR | Over The Rainbow |
| OTS | Open Theme Standard |
| OTS | O-Town Sound |
| OTSS | Only The Strong Survive |