| Acronym | Category | Meaning |
| BSTR | NASA Acronyms | Booster |
| BSTR | Chemistry Acronyms | Batch Stirred Tank Reactor |
| BSTS | Atmospheric Research Center Acronyms | Boost Surveillance And Tracking System |
| BSU | Atmospheric Research Center Acronyms | Beam Steering Unit |
| BSV | US Military Acronyms | Beach Support Vehicle |
| BSW | Uncategorized Acronyms | British Standard Whitworth (screw Thread) |
| BSWD | Computer And Internet Acronyms | BellSouth Intelligent Wireless Data Network |
| BSWKB | Chemistry Acronyms | Broken Supersymmetric Wentzel-Kramers-Brillouin |
| BSWS | US Military Acronyms | Boeing Software Standard |
| BSX | Uncategorized Acronyms | Bendigo Stock Exchange |
| BT | NASA Acronyms | Burn Time (Engine) |
| BT | SCUBA Diving Acronyms | Bottom Time |
| BT | Uncategorized Acronyms | Baronet; (ii) Bacillus Thuringiensis |
| BT | Uncategorized Acronyms | Bathythermograph -Bhutan (FIPS 10-4 Country Code; ISO 3166 Digram) - (ii) BitTorrent - (iii) British Telecommunications Plc |
| BT | Text Language Acronyms And Abbreviations | Bite This |
| BT | Medical Acronyms | Bowel Tones |
| BTA | Business And Finance | British Tourist Authority |
| BTA | SMS Chat And Text Acronyms | But Then Again... |
| BTA | Text Language Acronyms And Abbreviations | But Then Again |
| BTA | Text Language Acronyms And Abbreviations | Before The Attacks |
| BTAG | Atmospheric Research Center Acronyms | Biological Technical Assistance Group |
| BTB | Chemistry Acronyms | Bromothymol Blue |
| BTC | NASA Acronyms | Binary Time Code |
| BTC | NASA Acronyms | Bus Tie Contractor |
| BTCA | Chemistry Acronyms | Best Technology Currently Available |
| BTCC | Chemistry Acronyms | Biological Threat Characterization Centerpar |
| BTCC | Chemistry Acronyms | Bladder Transitional Cell Carcinomapar |
| BTCI | Human Genome Acronyms | BioPharmaceutical Technology Center Institute |
| BTDA | Chemistry Acronyms | 3,3',4,4'-benzophenonetetracarboxylic Dianhydride |
| BTDC | Chemistry Acronyms | Before Top Dead Center |
| BTDC | Chemistry Acronyms | Bulk Thermal Desorption Chamber |
| BTDT | Chatting Acronyms | Been There Done That |
| BTDT | US Army Acronyms (Slang) | Been There, Done That |
| BTDT | SMS Chat And Text Acronyms | Been There, Done That |
| BTDT | Text Language Acronyms And Abbreviations | Been There Done That |
| BTDTBTTS | US Army Acronyms (Slang) | Been There, Done That, Bought The T-Shirt |
| BTDTGTS | Text Language Acronyms And Abbreviations | Been There, Done That, Got The T-shirt |
| BTE | Chemistry Acronyms | Boltzmann Transport Equation |
| BTEM | Chemistry Acronyms | Band Target Entropy Minimization |
| BTEX | Chemistry Acronyms | Benzene, Toluene, Ethyl Benzene, And Xylene |
| BTF | Chemistry Acronyms | Biotransfer Factor |
| BTFO | Text Language Acronyms And Abbreviations | Back The F*ck Off |
| BTFO | Text Language Acronyms And Abbreviations | Bend The F*ck Over |
| BTGA | Chemistry Acronyms | Best Technology Generally Available |
| BTH | Medical Acronyms (Slang) | Bury The Hatchet - Accidently Leave A Surgical Instrument Inside A Patient. |
| BTHOOM | Text Language Acronyms And Abbreviations | Beats The Hell Out Of Me |
| BTI | Uncategorized Acronyms | Bacillus Thuringiensis Israelensis |
| BTID | Uncategorized Acronyms | Battlefield Target Identification Device |
| BTIS | Uncategorized Acronyms | Battlefield Target Identification System |
| BTIS | Chemistry Acronyms | Beam Tube Isolation System |
| BTK | Chemistry Acronyms | Bruton Tyrosine Kinase |
| BTMS | NASA Acronyms | Body Temperature Measuring System |
| BTN | Uncategorized Acronyms | Bhutan (ISO 3166 Trigram) - Bhutanese Ngultrum (ISO 4217 Currency Code) |
| BTN | Text Language Acronyms And Abbreviations | Better Than Nothing |
| BTO | Uncategorized Acronyms | Built To Order |
| BTOIYA | Text Language Acronyms And Abbreviations | Be There Or It's Your Ass |
| BTP | Uncategorized Acronyms | British Transport Police |
| BTP | Human Genome Acronyms | Biotechnology Training Programs |
| BTPPC | Chemistry Acronyms | Benzyltriphenylphosphonium Chloride |
| BTR | NASA Acronyms | Boom Time Remai-ni'ng |
| BTR | NASA Acronyms | Burn Time Remaining |
| BTR | NASA Acronyms | Bus Transfer |
| BTR | Uncategorized Acronyms | Bronetransporter (??? = ???????????????? (Heavy) Armoured (Personnel) Transporter) ? |
| BTS | US Govt. Acronyms | Bureau Of Transportation Statistics |
| BTS | Chemistry Acronyms | British Toxicology Society |
| BTSOOM | Medical Acronyms (Slang) | Beats The Shit Out Of Me |
| BTSOOM | SMS Chat And Text Acronyms | Beats The S*** Out Of Me |
| BTSOOM | Text Language Acronyms And Abbreviations | Beats The Sh*t Out Of Me |
| BTTT | Text Language Acronyms And Abbreviations | Back To The Top (pushing Forum Threads To The Top) |
| BTTT | Text Language Acronyms And Abbreviations | Bump To The Top (pushing Forum Threads To The Top) |
| BTU | NASA Acronyms | British Thermal Unit |
| BTU | NASA Acronyms | Bus Terminal Unit |
| BTU | Uncategorized Acronyms | British Thermal Unit |
| BTU | Atmospheric Research Center Acronyms | British Thermal Unit |
| BTU | Chemistry Acronyms | British Thermal Unit |
| BTUGA | Chemistry Acronyms | Bonded Tableau Unitary Group Approach |
| BTV | Chemistry Acronyms | Breakthrough Volume (sorption Capacity Measurement) |
| BTW | Chatting Acronyms | By The Way |
| BTW | Uncategorized Acronyms | By The Way |
| BTW | Computer And Internet Acronyms | By The Way |
| BTW | SMS Chat And Text Acronyms | By The Way |
| BTW | Text Language Acronyms And Abbreviations | By The Way |
| BTWBO | Text Language Acronyms And Abbreviations | Be There With Bells On |
| BTWITIAILW/U | Text Language Acronyms And Abbreviations | By The Way I Think I Am In Love With You |
| BTX | Chemistry Acronyms | Botulinum Toxin |
| BTX | Chemistry Acronyms | Benzene, Toluene, And Xylene |
| BTZ | Chemistry Acronyms | Below The Treatment Zone |
| BU | Atmospheric Research Center Acronyms | Bargaining Unit |
| BU | NASA Acronyms | Backup |
| BU | Uncategorized Acronyms | Bulgaria (FIPS 10-4 Country Code) - Burma (ISO 3166 Digram; Obsolete Since 1989) |
| BUAV | Uncategorized Acronyms | British Union For The Abolition Of Vivisection |
| BUC | NASA Acronyms | Buckhorn |
| BUC | NASA Acronyms | Backup Computer |
| BUFF | NASA Acronyms | Buffer |
| BUFR | Atmospheric Research Center Acronyms | Binary Universal Form For The Representation Of Meteorological Data |
| BUG | Uncategorized Acronyms | E -Battlefield Universal Gateway Equipment (buggy) |
| BUL | Uncategorized Acronyms | Bulgarian Language (ISO 639-2 Code) |
| BUN | Chemistry Acronyms | Blood Urea Nitrogen |
| BUN | Medical Acronyms | Blood Urea Nitrogen |
| BUNDY | Medical Acronyms (Slang) | But Unfortunately Not Dead Yet |