| Acronym | Definition |
|---|
| RSO➣Rick Simpson Oil (cannabis oil extraction) |
| RSO➣Radiation Safety Officer |
| RSO➣Radio-Sinfonie-Orchester (German: Radio Symphony Orchestra) |
| RSO➣Registered Student Organization (various universities) |
| RSO➣Registered Sex Offender |
| RSO➣Range Safety Officer |
| RSO➣Remote Shared Object |
| RSO➣Rapid Scan Operation |
| RSO➣Remote Spool Output |
| RSO➣Recognized Service Organization (Lutheran Church Missouri Synod) |
| RSO➣Research Services Office (various locations) |
| RSO➣Regional Security Officer |
| RSO➣Recognized Student Organization |
| RSO➣Roanoke Symphony Orchestra (Roanoke, VA) |
| RSO➣Rent Stabilization Ordinance (housing) |
| RSO➣Reactive search optimization (evolutionary computing technique) |
| RSO➣Retirement Services Officer |
| RSO➣Recognized Security Organization (International Maritime Organization ISPS code) |
| RSO➣Road Safety Officer (Australia) |
| RSO➣Robert Stigwood Organization |
| RSO➣Research and Statistics Office (various locations) |
| RSO➣Regina Symphony Orchestra (Canada) |
| RSO➣Reconnaissance Systems Officer |
| RSO➣Reduced Sign-On |
| RSO➣Robotic Service Orchestration (various companies) |
| RSO➣Regional Sales Office |
| RSO➣Rainbow Symphony Orchestra (Paris, France) |
| RSO➣Recovery Server Option |
| RSO➣Ralstonia Solanacearum |
| RSO➣Resident Space Object |
| RSO➣Radiological Safety Officer |
| RSO➣Repeat Sex Offenders (band) |
| RSO➣Rohingya Solidarity Organization (Burma) |
| RSO➣Regional Science Olympiad (education) |
| RSO➣Regimental Supply Officer (US Navy) |
| RSO➣Republic South Ossetia |
| RSO➣Regimental Signals Officer (UK) |
| RSO➣Registered Safety Officer (International Board of Environmental Health and Safety) |
| RSO➣Religious Support Office |
| RSO➣Rally Sport Ontario |
| RSO➣Riverside County Sheriff's Office (California) |
| RSO➣Remote Sales Officer |
| RSO➣Rapid Scan Operation (GOES satellite) |
| RSO➣Railway Sub - Office |
| RSO➣Retail Sales Officer |
| RSO➣Regional Supply Office |
| RSO➣Rainbow Service Organization (Peterborough, ON, Canada gay rights and information) |
| RSO➣Rogers Sportsnet Ontario (Canadian TV station) |
| RSO➣Refined Soybean Oil |
| RSO➣Resident Surgical Officer |
| RSO➣Rough Stud Opening (construction) |
| RSO➣Ridgewood Symphony Orchestra (Ridgewood, NJ) |
| RSO➣Remote Split Operations (military UAVs) |
| RSO➣Radiology Services Online (Celina, TX) |
| RSO➣Regional Service Officer |
| RSO➣Railway Sorting Office |
| RSO➣Rechargement et Soudure de l'Ouest (French welding company) |
| RSO➣Reconnaissance & Survey Officer |
| RSO➣Remote Service Object |
| RSO➣Right Salpingoophorectomy |
| RSO➣Repeated Spike Oxidation |
| RSO➣Revised Statute of Ontario (Canada) |
| RSO➣Reservoir Surveillance Operations |
| RSO➣Reported Significant Observation |
| RSO➣Runway Supervisory Officer |
| RSO➣Re-Entry Systems Operation |
| RSO➣Registered Student Organisation |
| RSO➣Reusable Software Object |
| RSO➣ROKA Staff Office |
| RSO➣Ravenna String Orchestra (Ravenna, OH) |
| RSO➣Reserve Supplement Officer |
| RSO➣Reconnaissance Staff Officer |
| RSO➣Ron Smolen Orchestra (Chicago, IL) |
| RSO➣Relationship Service Officer (finance; various organizations) |
| RSO➣Red Saber Order (gaming) |
| RSO➣Regional Standards Organization |
| RSO➣Road Service Outfit (bright yellow motorbike and sidecar used by AA patrols up until the 1960's) |
| RSO➣Rural Sub - Office |
| RSO➣Requirements Staff Officer (US DoD) |
| RSO➣Reservation Service Officer |
| RSO➣Removal Services Overseas |
| RSO➣Return Sales Order |