English abbreviations from orm to orta
- ORM (Operation Risk Management)
- ORMTA (Ontario Registered Music Teachers' Association)
- ORN (Oran Es Sénia Airport)
- ORNA (Oak Ridge Neighborhood Association)
- ORNL (Oak Ridge National Laboratory)
- ORO (Original Reusable Object)
- Or. Orat. (Orator ("Petitioner"), Oratorium ("Oratory"))
- ORP (Oxidation Reduction Potential)
- ORPC (Oundle Rifle and Pistol Club)
- ORQ (Ocean Racing Queensland Class Association, Inc.)
- ORR (Oak Ridge Reservation (U.S. DOE)||Office of Rail Regulation (UK government)||Office of Refugee Resettlement||(CIA) Office of Research and Reports||Operational Readiness Rate||Operational Readiness Review)
- ORRF (Operational Risk Research Foundation)
- ORS (Waterport Airport)
- ORSA (Oxacillin-resistant Staphylococcus aureus||Operations Research Society of America)
- ORSM (Off-Route Smart Mine)
- ORSMC (Off-Route Smart Mine Clearance)
- ORT (Northway Airport)
- ORTA (Office of Research and Technology Applications)
