| Acronym | Definition |
|---|
| SYSO➣Seattle Youth Symphony Orchestras (Washington) |
| SYSO➣Seguridad y Salud Ocupacional (Spanish: Occupational Safety and Health; governmental division; various locations) |
| SYSO➣Shelton Youth Soccer Organization (Connecticut) |
| SYSO➣Skaneateles Youth Soccer Organization (New York) |
| SYSO➣Swiss Youth Symphony Orchestra (Switzerland) |
| SYSO➣Starkville Youth Soccer Organization (Starkville, MS) |