| Abbreviation | Definition |
|---|---|
| OCPAC | Old Carey Performing Arts Club |
| OCTC | Orange County Track Club |
| OCV | Outdoor Club of Victoria |
| OCW | Ocean Club West |
| OCW | Oldies Club Wetterau |
| ODBC | Old Dominion Boat Club |
| ODC | Official Directioners Club |
| ODC | Oriental Dinghy Club |
| ODCB | Obedience Dog Club of Brisbane |
| ODCC | Old Dominion Corvette Club |
| ODCC | Out Door Country Club |
| ODCC | Oxford Downs Cricket Club |
| ODGC | Ocean Dunes Golf Club |
| ODGC | Ottawa Disc Golf Club |
| ODPC | Original Dulcimer Players Club |
| ODSC | Old Dominion Soccer Club |
| ODSC | Ontario Dual Sport Club |
| ODTC | Oakland Dog Training Club |
| ODTC | Oriole Dog Training Club |
| ODTC | Orlando Dog Training Club |