| Abbreviation | Definition |
|---|---|
| OHA | Oregon Hunters Association |
| OHF | Ontario Hockey Federation |
| OHL | Ontario Hockey League |
| OHP | Over Head Press |
| OHPA | Ohio Horseshoe Pitchers Association |
| OHPA | Olongapo Homing Pigeon Association |
| OHPA | Oregon Horseshoe Pitchers Association |
| OHSA | Ohio High School Athletic Association |
| OHSAA | Ohio High School Athletic Association |
| OHSAS | Ohio Hot Stove Baseball |
| OHW | Our Hardcore Wrestling |
| OJ | Optional Jumping |
| OJ | Outdoor Journey |
| OJC | Oaklawn Jockey Club |
| OJJB | Österreichischer Jiu Jitsu Bund |
| OJU | Oceania Judo Union |
| OJV | Österreichischer Judo Verband ( Austrian Judo Association) |
| OKK | Oslo KitesurfingKlubb |
| OKK | Oxfordshire Kadet Karting Club |
| OKS | Oklahoma Swimming, Inc. |