| Acronym | Definition |
|---|
| POSA➣President of South Africa |
| POSA➣Public Order and Security Act |
| POSA➣Partners of Sex Addicts |
| POSA➣Point of Sale Activation |
| POSA➣Pattern Oriented Software Architecture |
| POSA➣Person of Ordinary Skill in the Art (patent law) |
| POSA➣Politics of Open Source Adoption |
| POSA➣Proceed-on-Sight Authority (UK) |
| POSA➣Passive Optical Sample Assembly |
| POSA➣Pembroke Old Scholars' Association (Australia) |
| POSA➣Pinner Old Students Association (UK; alumni association) |
| POSA➣Parks and Open Space Advocates (Seattle, WA) |
| POSA➣Preliminary Operation Safety Analysis |
| POSA➣Payments Outstanding Suspense Account |
| POSA➣Pacific Ocean Shipping Agency (Egypt) |
| POSA➣Pomona College Student Art Gallery (Claremont, California) |
| POSA➣Pride of Sheffield Ave. (New York fire station) |