| Acronym | Meaning |
| OM | (USN Rating) Opticalman |
| OM | Mongolian Airlines (IATA airline code) |
| OM | On the Move |
| OM | Operational Manager |
| OM | Operational Manning |
| OM | Operations Module |
| OM | Operator Maintenance |
| OM | Operator's/Operation Manual |
| OM | Opticalman (US Navy rating) |
| OM | Orden Ministerial (Spanish) |
| OM | Order of Merit |
| OM | Organizational Maintenance |
| OM | Organized Militia |
| OM | Out for Maintenance |
| OM | Outer Marker |