| Abbreviation | Definition |
|---|---|
| OUAO | Once Upon an Orchestra |
| OUAS | Once Upon a Symphony |
| OUJO | Oxford University Jazz Orchestra |
| OUJS | Oxford University Jazz Society |
| OUMS | Oxford University Music Society |
| OVA | Ottava (Octave) |
| OVACWH | Oblong Viola Case with Hygrometer |
| OVD | O-Vibes Design |
| OVD | Ozarks Vintage Drum |
| OVI | Opera del Vocabolario Italiano |
| OVJ | Out Vile Jelly |
| OVMP | One Village Music Project |
| OVO | Octobers Very Own |
| OVOXO | October's Very Own X (drug ecstasy) O (oxycodone) |
| OWB | Old World Blues |
| OWB | Outside The Waist Band |
| OWO | Oakville Wind Orchestra |
| OYES | Ohio Youth Ensemble Stage |
| OYMP | Orillia Youth Music Program |
| OYO | Our Youth Orchestra |