| Abbreviation | Definition |
|---|---|
| BSI | Basic Shipping Instructions |
| BSI | Boeing Services International, Inc. |
| BSL | Biological Space Laboratory |
| BSL-4 | Biosafety Level 4 |
| BSM | Basic Storage Module |
| BSM | Booster Separation Motor |
| BSR | Back Surface Reflection |
| BSR | Basic System Release |
| BSR | Bite Status Register |
| BSRM | Booster Solid Rocket Motor |
| BSS | Backup System Services |
| BSTR | BooSTeR |
| BT | Burn Time |
| BTC | Binary Time Code |
| BTC | Bus Tie Contractor |
| BTMS | Body Temperature Measuring System |
| BTR | Boom Time Remaining |
| BTR | Burn Time Remaining |
| BTR | Bus TRansfer |
| BTU | Bus Terminal Unit |