| BSO | Bakersfield Symphony Orchestra 
| Others |
| BSO | Baltimore Symphony Orchestra
| Others |
| BSO | Banda Sonora Original
| Others |
| BSO | Bangkok Symphony Orchestra
| Others |
| BSO | Bangor Symphony Orchestra
| Others |
| BSO | Barents Sea Opening
| Others |
| BSO | Basco, Philippines
| Others |
| BSO | Basic Storage Object
| Others |
| BSO | Basic Subject Organization
| Others |
| BSO | Battalion Signal Officer
| Others |
| BSO | Beaverton Symphony Orchestra
| Others |
| BSO | Behavioural Supports Ontario
| Others |
| BSO | Beneficial Sharing Opportunities
| Others |
| BSO | Benefit Settlement Option
| Others |
| BSO | Better Scan Of
| Others |
| BSO | Bicycle Shaped Object
| Others |
| BSO | Bigelow Space Operations
| Others |
| BSO | Bike-Shaped Object
| Others |
| BSO | Bilateral Salpingo -Oophorectomy
| Others |
| BSO | Bilateral Salpingo Oopherectomy
| Others |
| BSO | Bilateral Salpingo Oophorectomy
| Others |
| BSO | Black Sports Online
| Others |
| BSO | Black Student Organization
| Others |
| BSO | Black Student Orientation
| Others |
| BSO | Block Storage Option
| Others |
| BSO | Blood Stock Only
| Others |
| BSO | Bloomingdale Soccer Organization
| Others |
| BSO | Bloomington Symphony Orchestra
| Others |
| BSO | Board of Strategy Operations
| Others |
| BSO | Board of Student Organizations
| Others |
| BSO | Bobcat Student Orientation
| Others |
| BSO | Bobsled and Skeleton Organization
| Others |
| BSO | Book Shaped Object
| Others |
| BSO | Border Services Officer
| Others |
| BSO | Boston Symphony Orchestra
| Others |
| BSO | Boston Systems Office
| Others |
| BSO | Bournemouth Symphony Orchestra
| Others |
| BSO | Brahminical Social Order
| Others |
| BSO | Brake System Optimisation
| Others |
| BSO | Brevard Symphony Orchestra
| Others |
| BSO | Bright Shiny Object
| Others |
| BSO | Bright Shiny Objects
| Others |
| BSO | Broad System of Ordering
| Others |
| BSO | Broward Sheriff's Office
| Others |
| BSO | Brueckner Spin Orbitals
| Others |
| BSO | Bruins Safe Online
| Others |
| BSO | Budget Submitting Office
| Others |
| BSO | Buffalo Street Outlaws
| Others |
| BSO | Bus Service Operation
| Others |
| BSO | Business Services Online
| Others |
| BSO | Business Support Operation
| Others |
| BSO | Business Support Operator
| Others |