| ORS | Oregon Revised Statutes | |
| ORS | Office of Research Services | |
| ORS | Office of Research and Statistics (Social Security) | |
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| ORS | Office of Research Support (various schools) | |
| ORS | Observatoire Régional de la Santé | |
| ORS | Oral Rehydration Solution | |
| ORS | Orthopaedic Research Society | |
| ORS | Oral Rehydration Salts | |
| ORS | Output Record Separator | |
| ORS | Office of Retirement Services (Michigan) | |
| ORS | Operationally Responsive Space (US DoD) | |
| ORS | Oil Recovery System | |
| ORS | Octopole Reaction System (mass spectrometry) | |
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| ORS | Office of Regulatory Staff | |
| ORS | Oak Ridge Schools (Tennessee) | |
| ORS | Office for Recreation and Sport (Australia) | |
| ORS | Operation Resolute Support (NATO) | |
| ORS | Online Reporting System | |
| ORS | Operational Research Society | |
| ORS | Overseas Research Scholarships (postgraduate award; UK) | |
| ORS | Onion River Sports (Montpelier, VT) | |
| ORS | O-Ring Seal | |
| ORS | Oneida Research Services (various locations) | |
| ORS | Oculo-Respiratory Syndrome | |
| ORS | Obligated Reserve Section | |
| ORS | Order Routing System | |
| ORS | Operational Requirements Statement | |
| ORS | Over Range Station | |
| ORS | Ocean Rowing Society | |
| ORS | Operational Research Section | |
| ORS | Online Recruiting Station | |
| ORS | Occurrence Reporting Section | |
| ORS | Omnificent Role-playing System (gaming) | |
| ORS | Oregon Radiological Society | |
| ORS | Occurrence Reporting System | |
| ORS | Orbiter Refueling System (NASA) | |
| ORS | Office of Records Services (US government) | |
| ORS | Offensive Radar System | |
| ORS | Online Reference System | |
| ORS | Optical Routing Switch (Corvis) | |
| ORS | OpRisk Suite | |
| ORS | Orthopaedic Research Society ROC (Taiwan) | |
| ORS | On-Line Reprogramming System | |
| ORS | Open Replicator for Symmetrix (EMC) | |
| ORS | Office Repeater Shelf | |
| ORS | Open Registration System | |