| Acronym | Definition |
|---|
| OPSA➣Office of Professional School Advising (Texas A&M University) |
| OPSA➣Oklahoma Political Science Association |
| OPSA➣Oxidation Phenomena in Severe Accidents (project; EU) |
| OPSA➣Odontologia Personalizada SA (Portuguese: Personalized Dentistry) |
| OPSA➣OSSTMM (Open Source Security Testing Methodology Manual) Professional Security Analyst (certification; Institute for Security and Open Methodologies) |
| OPSA➣Oregon Public Safety Academy |
| OPSA➣Organismes Paritaires Collecteurs Agrées |