| OSAT | Observing Systems and Advanced Technology
| Others |
| OSAT | Office for the Study of Automotive Transportation
| Others |
| OSAT | Oklahoma Subject Area Tests
| Others |
| OSAT | On Site Assessment and Training
| Others |
| OSAT | One School At a Time
| Others |
| OSAT | One Step at A Time
| Others |
| OSAT | Online Schooling And Training
| Others |
| OSAT | Online Structure Assessment Tool
| Others |
| OSAT | Open Source Appropriate Technology
| Others |
| OSAT | Open Space Assessment Tool
| Others |
| OSAT | Open-Source Appropriate Technology
| Others |
| OSAT | Oregon Statewide Assessment Tests
| Others |
| OSAT | Out of Service Analog Test
| Others |
| OSAT | Out-Of-Service Analog Test
| Others |
| OSAT | Outsource Semiconductor Assembly and Test
| Others |
| OSAT | Outsourced Semiconductor Assembly and Test
| Others |
| OSAT | Overleg Scholing Arbeidsmarkt Theatertechniek
| Others |
| OSAT | Ozone Source Apportionment Technology
| Others |