| Acronym | Definition |
|---|
| OPSO➣Ouachita Parish Sheriff Office (Monroe, LA) |
| OPSO➣Operations Officer |
| OPSO➣Older People Speak Out (Australia) |
| OPSO➣On Public Service Only (postage; New Zealand) |
| OPSO➣Osteopathic Physicians and Surgeons of Oregon (Portland) |
| OPSO➣Over Pressure Shut-Off (valve) |
| OPSO➣Open Software (Italian software and web services company) |
| OPSO➣Office of Pipeline Safety Operations (US DOT) |
| OPSO➣Overlapping Pairs Sparse Occupancy Test (random number generators) |