| Abbreviation | Definition |
|---|---|
| OCA | Oregon Cattlemen's Association |
| OCFB | Oakland County Farm Bureau |
| OCFB | Orange County Farm Bureau |
| OCIA | Organic Crop Improvement Association |
| OCPA | Oklahoma Club Pig Association |
| ODA | Ohio Department of Agriculture |
| ODAC | Olde Dominion Agricultural Complex |
| ODFAP | Ontario Dairy Farm Accounting Project (Mississauga, Ontario, Canada) |
| OFA | Ontario Federation of Agriculture |
| OFAR | Office of Foreign Agricultural Relations |
| OFAR | On Farm Adaptive Research |
| OFAR | On- Farm Adaptive Research |
| OFB | Old Farmer's Ball |
| OFB | Oregon Farm Bureau |
| OFC | Open Farm Community |
| OFCAF | On-Farm Climate Action Fund |
| OFD | On Farm Development |
| OFD | On-Farm Development |
| OFDS | On Farm Data Sharing |
| OFFC | Our Family Farms Coalition |