| Abbreviation | Definition |
|---|---|
| OMAC | Old Man's Aircraft Company |
| OMAC | Onondaga Model Aircraft Club |
| OMAO | Office of Marine and Aviation Operations |
| OMAO | Office of Marine Aviation Operations |
| OMAS | Oregon Miniature Aircraft Squadron |
| OMC | Observer Member Of The Crew |
| OOM | FAST SPEED WITH 'Z' UP FRONT! |
| OPE | Old People Early |
| OPKC | ICAO designationO - AsiaP - PakistanKC- Karachi (Jinnah International Airport) |
| ORAA | Office of Regional Aviation Assistance |
| ORAA | Ogden Regional Airport Association (Utah) |
| ORCA | Optical and RF Constellation on Aircraft |
| ORS | Outside Release Switch |
| ORTIA | O R Tambo International Airport |
| OSM | Onboard Storage Management |
| OSMF | Onboard Storage Management Function |
| OTU | Operational Training Unit |
| OV | Operating Velocity |
| OWE | OVERWING. EMERGENCY EXIT |
| OZ | Observation Zero |