| Acronym | Definition |
|---|
| OPAA➣Ohio Prosecuting Attorneys Association |
| OPAA➣Office of Post Award Administration (Oregon State University and University of Texas) |
| OPAA➣Organization for the Prevention of AIDS in Africa (est. 2001) |
| OPAA➣Outstanding PolyU (Polytechnic University) Alumni Award (Hong Kong) |
| OPAA➣Other Public Access Areas (water management) |
| OPAA➣Oregon Political Accountability Act |