English abbreviations from orta to osa
- ORTA(Office of Research and Technology Applications)
- ORTF(Office de Radiodiffusion Television Francaise)
- ORTSU(Organized Reserve Training Service Training Unit)
- ORU(Oruro Airport)
- ORV(Robert (Bob) Curtis Memorial Airport (FAA: D76))
- ORW(Olentangy River Wetland Research Park)
- ORX(Operational Receiver)
- ORY(Orly International Airport)
- OS(Operating System)
- O.S.(Left eye)
- OS/2(Operating System/2)
- OS/360(IBM 360 operating system (1960s))
- OS&D(Over, Short & Damage (Report))
- OS/OD(Overall size/overall diameter)
- OS2(Operating System/2)
- OSA(Overseas Contingency Operation Support Assignments)
- O.S.A.(Ordo [Eremitarum] Sancti Augustini (Augustinians))