| Abbreviation | Definition |
|---|---|
| OLF | Occupational License Fee |
| OLF | On- Line Form |
| OLM | Olmsted County, Ohio |
| OLR | Office of Legislative Research |
| OLRB | Ontario Labour Relations Board |
| OLT | Oregon Labor Trends |
| OLY | Olympia, Washington |
| OMA | Office of Metropolitan Architecture |
| OMAFRA | Ontario Ministry of Agriculture, Food and Rural Affairs |
| OMAFRA | Ontario Ministry of Agriculture, Food and Rural Services |
| OMAP | Office of Medical Assistance Programs |
| OMB | Ontario Municipal Board |
| OMC | Office of Managed Care |
| OMERS | Ontario Municipal Employees Retirement System |
| OMF | Office of the Undersecretary/ Management and Finance |
| OMI | Ocean- Merced- Ingleside, California |
| OMI | Office of Medical Investigator |
| OML | Oklahoma Municipal League |
| OMMB | Ontario Milk Marketing Board (1965August 1, 1995 when it was replaced by the Dairy Farmers of Ontario) |
| OMMB | Ontario Milk Marketing Board (1965—August 1, 1995 when it was replaced by the Dairy Farmers of Ontario) |