| Acronym | Definition |
|---|
| BSO | Baltimore Symphony Orchestra |
| BSO | Broward Sheriff's Office (Broward County, Florida) |
| BSO | Boston Symphony Orchestra |
| BSO | Bournemouth Symphony Orchestra (UK) |
| BSO | Bicycle Shaped Object (design) |
| BSO | Business Services Online (Social Security Administration) |
| BSO | Beroepssecundair Onderwijs (Dutch) |
| BSO | Bilateral Salpingo-Oophorectomy (surgical removal of both fallopian tubes and ovaries) |
| BSO | Berliner Sinfonie Orchester (German: Berlin Symphony Orchestra) |
| BSO | Banda Sonora Original (Spanish, soundtrack) |
| BSO | British School of Osteopathy (London, UK) |
| BSO | Broad System of Ordering (subject classification system) |
| BSO | British Scouting Overseas (UK) |
| BSO | Black September Organization (Palestinian Guerilla Group) |
| BSO | Bulgarian Symphony Orchestra |
| BSO | Berkeley Symphony Orchestra (Berkeley, CA, USA) |
| BSO | Bismuth Silicon Oxide |
| BSO | Basco, Philippines (Airport Code) |
| BSO | Business Services Office (various locations) |
| BSO | Border Services Officer (Canada Border Services Agency) |
| BSO | Baloch Student Organization |
| BSO | Bolton Symphony Orchestra (UK) |
| BSO | Blues Society of the Ozarks (Springfield, MO) |
| BSO | Branson School Online (Colorado) |
| BSO | Black Students' Organization (Carroll College, Waukesha, Wisconsin USA) |
| BSO | Budget Submitting Office |
| BSO | Bright Shiny Object |
| BSO | Bach Society Orchestra (various schools) |
| BSO | Benzene-Soluble Organics |
| BSO | Business Support Organization |
| BSO | Brooklyn Symphony Orchestra (Brooklyn, NY) |
| BSO | Basic Security Option |
| BSO | Basingstoke Symphony Orchestra (Hampshire, UK) |
| BSO | Banque Saint Olive (French bank) |
| BSO | Building Safer Organisations (Humanitarian Accountability Partnership International) |
| BSO | Boating Safety Officer |
| BSO | Baytown Symphony Orchestra (Baytown, TX) |
| BSO | Baggage Service Office |
| BSO | Bremerton Symphony Orchestra (Bremerton, WA) |
| BSO | Business System Owner |
| BSO | Base Supply Office |
| BSO | Broward Symphony Orchestra (Ft. Lauderdale, FL) |
| BSO | Ballon Stratosphérique Ouvert (French: Open Stratospheric Balloon) |
| BSO | Battalion/Brigade Signal Officer |
| BSO | Broadband Switch Operations (Sprint) |
| BSO | Battlespace Objective (US Army) |
| BSO | Bookstore Officer (Church of Scientology) |
| BSO | Buyer Sign-Off |
| BSO | Brueckner Spin Orbital(s) |
| BSO | Business Service Option(s) |
| BSO | Bristol Symphony Orchestra |
| BSO | Ballistics Services Office (US DoD) |