| Abbreviation | Definition |
|---|---|
| OSMA | Oklahoma State Medical Association |
| OSMA | Open Space Maintenance Association |
| OSMA | OSMAOrthopedic Surgical Manufacturer’s Association |
| OSMA | OSMAOrthopedic Surgical Manufacturers Association |
| OSPE | Ontario Society of Professional Engineers |
| OSSS | Oregon Society of Soil Scientists |
| OSTA | Optical Storage Technology Association |
| OSTD | Ontario Society for Training and Development |
| OTA | Ontario Trucking Association |
| OTA | Orthodontic Technicians Association |
| OTAI | Oil Technologists Association of India |
| OTPM | Office Total Productive Maintanance |
| OTTIAQ | Ordre des Traducteurs, Terminologies, et Interpretes Agrees du Quebec |
| OVA | Open Virtualization Alliance |
| OVID | Offshore Vessel Inspection Database |
| OXA | Ottawa Excutives` Association |
| P.Eng. | Professional Engineer (used in Canada; =PE in USA) |
| P.L.ENG | Professional Licensee Engineering |
| P.Tech | Professional Technologist |
| P3P | Points Three Plus international |