| Acronym | Definition |
|---|
| HSO | Hiroshima Symphony Orchestra (Japan) |
| HSO | HIPAA (Health Insurance Portability and Accountability Act) Security Officer |
| HSO | Halion Symphonic Orchestra |
| HSO | Thermal Enhanced Small Outline Package |
| HSO | Hartford Symphony Orchestra |
| HSO | Health and Safety Officer |
| HSO | Huntsville Symphony Orchestra |
| HSO | Health Sciences Online |
| HSO | Homeostatic Soil Organism |
| HSO | Health Service Organizations |
| HSO | Housing Support Officer (various organizations) |
| HSO | Health Service Ombudsman (UK) |
| HSO | Hereford String Orchestra (est. 1958; UK) |
| HSO | Haitian Student Organization (various universities) |
| HSO | Honor Super Omnia (Kappa Delta Rho fraternity) |
| HSO | Human Service Organization |
| HSO | Human Services Officer |
| HSO | Hershey Symphony Orchestra (Hershey, PA) |
| HSO | Hot Sports Opinion |
| HSO | High-Speed Online (Time Warner Cable) |
| HSO | Healthcare Support Office (United States Navy) |
| HSO | Hot Spot Operator (wireless access) |
| HSO | Habitation and Station Operations |
| HSO | Hull Street Outlet (Richmond, VA) |
| HSO | Horizontal Sight Offset (traffic engineering) |