| Abbreviation | Definition |
|---|---|
| OSL | Ontario Safety League |
| OSL | Operation Starting Line |
| OSL | Overseas Service Learning |
| OSLC | Oregon Social Learning Center |
| OSLT | Occupation-Specific Language Training |
| OSM | Open Street Map or OpenStreetMap |
| OSM | OpenStreetMap (http://www.openstreetmap.org) |
| OSMF | OpenStreetMap Foundation |
| OSPREY | Ocean Science Program in Recruitment and Education for Youth |
| OSR | Office of School Readiness |
| OSS | Out of School Suspension |
| OSSE | of the State Superintendent of Education |
| OSSE | Office of the State Superintendent of Education |
| OST | On Site Training |
| OSTA | Oklahoma Science Teachers Association |
| OSTA | Oregon Science Teachers Association |
| OSU | Outstanding Satisfactory Or Unsatisfactory |
| OSY | Out of School Youth |
| OSY | Outstanding Student of the Year |
| OT | Occupational Therapy |