| Regional Campus Organizer | Academic & Science |
| Rochefort | Airport Code |
| Rental Certificate of Occupancy | Business |
| Ramco Energy, PLC | Business |
| Refined Chemical Oil | Business |
| Rotary CutOff | Business |
| Regional Coordinating Organization | Business |
| Recycling Council of Ontario | Business |
| Royalco Resources Ltd | Business |
| Rental Certificate of Occupany | Business |
| Regenerative Catalytic Oxidizer | Chemistry |
| Regional Church Office | Community |
| Residential Communities Office | Community |
| Regional Coordinating Officer | Community |
| Registered Community Organizations | Community |
| Reno Chamber Orchestra | Community |
| Recreation and Conservation Office | Community |
| Royal Concertgebouw Orchestra | Community |
| Recovery Community Organization | Community |
| Registration Confirmation | Computing |
| Ratio of Correct Object | Computing |
| Reusable Content Objects | Computing |
| Residual Crude Oil | General |
| Race Chaser Online | General |
| Racing Car Online | General |
| Racing Cars Organisation | General |
| Race Cars Open | General |
| Rally Car Other | General |
| Rear Cargo Organizer | General |
| Road Condition Observer | General |
| Real Cost Of Ownership | General |
| Resource Connections of Oregon | General |
| Route Crossable Objects | General |
| Remote Communication Outlet | General |
| Recency Complexity and Overhead | General |
| Remote Communications Outlets | General |
| Relational Capital of Organizations | General |
| Rapid Capabilities Office | General |
| Refugee Center Online | General |
| Red Cells Only | General |
| Rapid Change Over | General |
| Responsible Corporate Officer | General |
| Revenue Cycle Outsourcing | General |
| Rifle Combat Optic | General |
| Ring Cycle Option | General |
| Remote Communications Outlet | Governmental |
| Regional Consular Office | Governmental |
| Reservations, Commitments, and Obligations | Governmental |
| Reports Clearance Officer | Governmental |
| Regional Compliance Officer | Governmental |
| Regional Currency Office | Governmental |
| Regional Co-ordination Officer | Governmental |
| Regional Control Office | Governmental |
| Regional Certification Officer | Governmental |
| Research Compliance Officer | Governmental |
| Risk & Control Officer | Governmental |
| Resident Coordinator’s Office | Governmental |
| Russian Carnivorous Octopi | Medical |
| Regional Contracting Office | Military and Defence |
| Regional Communications Officer | Military and Defence |
| Radar Control Operator | Military and Defence |
| Rifle Combat Optics | Military and Defence |
| Remote Computing Options | Networking |
| Saint Agnant Airport, Rochefort, France | Regional |
| Regional Care Organizations | Regional |
| Range Control Officer | Space Science |
| Rio Rico Resort Country Club | Sports |
