| Acronym | Definition |
|---|
| OStR➣Oberstudienrat (Austria, Europe) |
| OStR➣Orchestre Symphonique de Trois-Rivières (Canada) |
| OStR➣Optimum Speed Tilt Rotor (Karem Aircraft) |
| OStR➣Optical Single Transporter Recording |
| OStR➣Oblates of St. Therese Reformed (religious order) |
| OStR➣On-Site Technical Representative |