| Acronym | Definition |
|---|
| BOS | Boston Red Sox (baseball team) |
| BOS | Boston, MA, USA - Logan International Airport (Airport Code) |
| BOS | Board of Supervisors (municipal government body; various locations) |
| BOS | Bank of Sharjah (United Arab Emirates) |
| BOS | Board Of Studies |
| BOS | Book of Shadows |
| BOS | Bantuan Operasional Sekolah (Indonesian: School Operating Assistance) |
| BOS | Branch of Service |
| BOS | Bill of Sale |
| BOS | Business of Science |
| BOS | Bottom of Steel (manufacturing) |
| BOS | Bank of Scotland |
| BOS | Bank of Singapore |
| BOS | Borneo Orangutan Survival (Foundation; formerly Balikpapan Orangutan Society) |
| BOS | Blue Ocean Strategy (book) |
| BOS | Business Operating System |
| BOS | Brotherhood of Steel |
| BOS | Burnout Syndrome (behavioral health) |
| BOS | Bank of Slovenia |
| BOS | Business of Software (conference) |
| BOS | Behörden und Organisationen mit Sicherheitsaufgaben (German: Public Safety Authorities and Organizations) |
| BOS | Business Outsourcing Solutions (various companies) |
| BOS | Best of Show |
| BOS | Business Outlook Survey (various organizations) |
| BOS | Balance of System |
| BOS | Boulder Open Space (Colorado) |
| BOS | Best Opposite Sex (animal competition award) |
| BOS | Balance of State |
| BOS | Beginning of Stream |
| BOS | Business Operations Support |
| BOS | Batch Operating System |
| BOS | Block Operating System |
| BOS | Business Object Superviseur |
| BOS | Bronchiolitis Obliterans Syndrome (respiratory disease) |
| BOS | Banking Ombudsman Scheme (India) |
| BOS | Better Online Solutions (Israel) |
| BOS | Barber of Seville (opera) |
| BOS | Battlefield Operating Systems |
| BOS | Base Operating System |
| BOS | Base of Support (physical therapy) |
| BOS | Base Operating Support |
| BOS | Basic Operating System |
| BOS | British Origami Society (UK) |
| BOS | Back Office System |
| BOS | Basic Oxygen Steelmaking |
| BOS | Bank of Switzerland |
| BOS | Backup proxy Server |
| BOS | Breathing Oxygen System |
| BOS | Base of Skull (anatomy) |
| BOS | Balikpapan Orangutan Society |
| BOS | Bilbao Orkestra Sinfonikoa (Spanish: Bilbao Symphony Orchestra; Bilbao, Spain) |
| BOS | Binary Device Object Store |
| BOS | Book of Style (American Association for Medical Transcription) |
| BOS | Basic Overseer Server |
| BOS | Books over Seas (Palos Verdes Peninsula High School; California) |
| BOS | Broadband Operating System (Enron) |
| BOS | Base Operation Support |
| BOS | Bromsgrove Operatic Society (UK) |
| BOS | Business Office Supervisor |
| BOS | Boots of Speed (NetHack) |
| BOS | Book of Occasional Services (Episcopal Church) |
| BOS | Base Operations Services |
| BOS | Buschke-Ollendorff Syndrome |
| BOS | Business Optimization Server (computing) |
| BOS | Bit Oriented Signaling (AT&T) |
| BOS | Bright Object Sensor |
| BOS | British Orthodontics Society |
| BOS | Business Operations Support (Sprint) |
| BOS | Billing Output Specification (Sprint) |
| BOS | Business Object Summit |
| BOS | Backup Operating System |
| BOS | Brazil Offshore Services |
| BOS | Brothers of Struggle (gang faction) |
| BOS | Battalion Orderly Sergeant |
| BOS | Boston Celtics Limited Partnership (stock symbol) |
| BOS | Base of Salt |
| BOS | Basic Organization Structure (Army) |
| BOS | Ball of Steel |
| BOS | Boyfriend Over Shoulder |
| BOS | Behavior Observation System |
| BOS | Brotherhood of Soldiers (gaming clan) |
| BOS | Beacon Only Site (FAA radar) |
| BOS | Barksdale AFB, Louisiana (designator) |
| BOS | Boss over Shoulder |
| BOS | Bell Operating System |
| BOS | Branchiootic Syndrome |
| BOS | Business Operating Standards |
| BOS | Battlefield Operation Systems |
| BOS | Budget Operating System (Army) |
| BOS | Bombay Orthopedic Society |
| BOS | Back-Off Sub (drilling industry) |
| BOS | Basic Officer School |
| BOS | Bootable Operating System |
| BOS | Base Operating Supplies |
| BOS | Budget Obligation System |
| BOS | Balance of Sale |
| BOS | Background Operating System |
| BOS | Brother Over Shoulder |
| BOS | Broadband on Screen (TV Remote Control) |
| BOS | Bless Our Souls |
| BOS | Binary Orthogonal Signal |
| BOS | Bands Of Separation |