sort by Rank | Alpha
| Possible Meanings | Rank |
|---|
| Occupant Protection Use | ***** |
| Oceanteam Power Umbilical | **** |
| Optical Pickup Unit | **** |
| Optical Pick Up | *** |
| Osaka Prefecture University | *** |
| Oil Pumping Units | *** |
| Oregon Parents United | *** |
| Online Publishing Update | *** |
| Operative Psychiatric Units | ** |
| oocytes per pickup | ** |
| Okayama Prefectural University | ** |
| Operation Processing Units | ** |
| Optical Payload Unit | * |
| Overspeed Protection Unit | * |
| Operational Policing Units | * |
| Orangutan Protection Unit | * |
| Owatonna Public Utilities | * |
| Octal Program Updating | * |
| Order To Prohibit Use | * |
| Ovarium Pick up | * |
| Odesa Polytechnical University | * |
| Official Publications of the Unit | * |
| Original Parent Unit | * |