| Acronym | Definition |
|---|
| BYSO | Bring Your Significant Other |
| BYSO | Boston Youth Symphony Orchestras |
| BYSO | Bellevue Youth Symphony Orchestra (Bellevue, Washington) |
| BYSO | Berkshire Youth Symphony Orchestra (UK) |
| BYSO | Bastrop Youth Soccer Organization (Bastrop, LA) |
| BYSO | Bastrop Youth Soccer Organization (Bastrop, TX) |
| BYSO | Brant Youth Symphony Orchestra (Ontario, Canada) |
| BYSO | Binghamton Youth Symphony Orchestra (Binghamton, New York) |
| BYSO | Bay Youth Symphony Orchestra (Norfolk, VA) |
| BYSO | Bilkent Youth Symphony Orchestra (Turkey) |
| BYSO | Bromley Youth Symphony Orchestra (UK) |
| BYSO | Bais Yisroel Shabbos Observer |
| BYSO | Brush Your Shoulders Off |