| Acronym | Meaning |
 | BRITE | Basic Research In Industrial Technologies Europe |
 | BRL | Ballistics Research Laboratory |
 | BRMS | Basin Rainfall Monitoring System |
 | BRS | Bibliographic Retrieval Service |
 | BSAC | Biotechnology Science Advisory Committee |
 | BSD | Berkeley Software Distribution |
 | BSD UNIX | Berkeley Software Distribution UNIX |
 | BSDI | Berkeley Software Design |
 | BSI | British Standards Institute |
 | BSR | Budget Surplus Report |
 | BSR | Bus Select Relay |
 | BSRN | Boulder Science Resource Network |
 | BSRN | Baseline Surface Radiation Network |
 | BSTS | Boost Surveillance And Tracking System |
 | BSU | Beam Steering Unit |
 | BTAG | Biological Technical Assistance Group |
 | BTU | British Thermal Unit |
 | BU | Bargaining Unit |
 | BUFR | Binary Universal Form For The Representation Of Meteorological Data |
 | BUREC | Bureau Of Reclamation |
 | BUS | Business Operations |
 | BUV | Backscatter Ultraviolet |
 | BV | Building Ventilation |
 | BWC | Biological Weapons Convention |
 | BWI | Baltimore-Washington International Airport |
 | BWIP | Basalt Waste Isolation Project |
 | BX | Base Exchange |
 | BXA | Bureau Of Export Administration |
 | C | A Programming Language Used Extensively In Systems Software |
 | C&C | Consultation And Cooperation Agreement |
 | C&DH | Command And Data Handling |
 | C&DM | Configuration And Data Management |
 | C++ | An Object-oriented Programming Language Based On C |
 | C/D | Integrated Phase C And Phase D Contract |
 | C2F3CL3 | CFC-113 |
 | C2FBR2 | Halon 2402 |
 | CA | Citizen Act |
 | CAA | Clean Air Act |
 | CAA | Concepts Analysis Agency |
 | CAAA | Clean Air Act Amendments |
 | CAAC | Civil Aviation Administration Of China |
 | CAALS | Consortium On Automated Standards |
 | CAAP | Composition And Acidity Of SE Asian Precipitation |
 | CAB | CCSM Advisory Board |
 | CABALS | Carrier Balloon System |
 | CAC | Central Analysis Center (NMC) |
 | CAC | Climate Analysis Center |
 | CAC | California Administrative Code |
 | CACGP | Commission On Atmospheric Chemistry And Global Pollution |
 | CACM | Communications Of The ACM |