sort by Rank | Alpha
| Possible Meanings | Rank |
| Ongoing Strategic Review | **** |
| On Station Research | **** |
| Ocean State Republican | **** |
| OF SPONSORED RESEARCH | **** |
| Office of State Review | **** |
| Of Student Representatives | *** |
| One Shot Racing | *** |
| Office of School Relations | *** |
| Open Session Routing | *** |
| Organization of Student Representatives | *** |
| Other Side River | *** |
| Ocean Surface Radar | *** |
| Overall State Record | *** |
| Organization of the Spring | *** |
| Ontario Stewardship Rangers | *** |
| Organization Study and Review | *** |
| Open Space Recreation | *** |
| Operating System Release | *** |
| Office for Sponsored Research | *** |
| Outreach Screening Referral | *** |
| Office of Systemic Reform | *** |
| Own Source Revenue | *** |
| Office of State Register | *** |
| Ontario School Record | *** |
| Open Space Requirements | *** |
| Open Space and Recreation | *** |
| Office of Sport and Recreation | *** |
| Online Service Request | *** |
| Order of the Sacred Rose | *** |
| Old School Racings | *** |
| Open Space Ratio | *** |
| Open Space Residential | ** |
| Office of Student Research | ** |
| object subject ratio | ** |
| Object-Specific Reasoner | ** |
| Objectively Safety Rating | ** |
| Oblique section reconstruction | ** |
| observed survival rate | ** |
| Occlusal Stability Ratio | ** |
| Office of Survey Research | ** |
| one step removed | ** |
| Open structure rhinoplasty | ** |
| open surgical repair | ** |
| overall safety rating | ** |
| overall severity rate | ** |
| overall survival rate | ** |
| oxidant stress rate | ** |
| Open Speech Repository | ** |
| Operational Safety Requirements | ** |
| Officer Summary Record | ** |
| Officer Selection Record | ** |
| Offsite Source Recovery | ** |
| Old Spanish Road | ** |
| Old School Records | ** |
| organized spontaneous reporting system | ** |
| overall survival from recurrence | ** |
| Office for Survey Research | ** |
| Output Shift Register | ** |
| Open Space Resources | ** |
| OSCAR Satellite Report | ** |
| One Sentence Resume | ** |
| Oil Spill Research | ** |
| Operating System Resource | ** |
| Over Sampling Ratio | ** |
| Occoneechee Scout Reservation | ** |
| Optical solar reflectors | ** |
| Offshore Safety Representatives | ** |
| Ottawa Sports Radio | ** |
| Office of Services Review | ** |
| Oberlin Stray Rescue | ** |
| Online Server Reminder | ** |
| Output Status Register | ** |
| Office for Survey | ** |
| Office of Safety Regulation | ** |
| Odor Stain Remover | ** |
| Official and Statistical Register | ** |
| Orthopedic Sport Rehab | ** |
| Of School Reform | ** |
| Oil Steam Ratio | ** |
| Ontario Student Records | ** |
| Onward Supply Relief | ** |
| Open Space Ratios | ** |
| Odor and Stain Remover | ** |
| Oil Stain Remover | ** |
| Open Systems Recognition | ** |
| Oklahoma State Reformatory | ** |
| Operational Switch Replacement | ** |
| Office of Scholarly Resources | ** |
| Operations Statistical Reporting | ** |
| OCaml Standard Recommandation | ** |
| Oil Sand Removal | ** |
| Operational Support Requirements | ** |
| Order Status Report | ** |
| Outreach Screening and Referral | ** |
| OPERATIONS SUPPORT ROOM | ** |
| Office of Special Reclamation | * |
| Old School Ravers | * |
| Ole Spring Relief | * |
| Operating System Requirements | * |
| Outside Sales Representatives | * |
| Officina Sussidiaria Ricambi | * |
| Office of Survey and Review | * |
| Operational Statistical Reporting | * |
| Optical Surface Reflectors | * |
| Organization of Student Reps | * |
| Occupancy Sensor Remote | * |
| Office for Scientific Research | * |
| OAK Software Repository | * |
| Office of Schedules and Reservations | * |
| Operand Storage Register | * |
| OptiStreams Satellite Router | * |
| Operating Systems Research | * |
| OCCUPATIONAL SURVEY REPORTS | * |
| Object Sighting Report | * |
| Oil Shale Reserves | * |
| Operational Safety Reviews | * |
| Off Site Resources | * |
| Officer Service Record | * |
| Officer Summary Records | * |
| Official State Register | * |
| Operating Safety Requirements | * |
| Operating System Research | * |
| Operating Systems and Related | * |
| Occluded Surface Reconstruction | * |
| Outside Security Router | * |
| Oakland Software Repository | * |
| Ocean Sediments and Rocks | * |
| Office of Scientific Review | * |
| Office of ScientificResearch | * |
| Office of Sponsored Research | * |
| Office of Standards and Regulations | * |
| Office of Surface Reclamation | * |
| Official Site of the Ryder | * |
| Oilfield Supply and Rental | * |
| Okawville Silurian Reef | * |
| Online Source Register | * |
| Osmotic Stress Research | * |
| Otter Southern River | * |
| Overburden Sampling References | * |
| Overlake School Redmond | * |
| Ozark Scenic Rivers | * |