| Acronym | Definition |
|---|
| YSO➣Yellow Springs, Ohio |
| YSO➣Young Stellar Object |
| YSO➣Yale Symphony Orchestra |
| YSO➣Yamagata Symphony Orchestra (Japan) |
| YSO➣Youth Service Officer |
| YSO➣Youth Soccer Organization (various organizations) |
| YSO➣Yttrium Oxyorthosilicate |
| YSO➣Youngstown Symphony Orchestra (Youngstown, OH) |
| YSO➣York Symphony Pops Orchestra |
| YSO➣Ylivieskan Sosiaalialan Oppilaitos (Finnish: Ylivieska Social Institution; Ylivieska, Finland) |
| YSO➣Youth Sector Organisation (Singapore) |