| Acronym | Definition |
|---|
| BAR | Browning Automatic Rifle |
| BAR | Best Available Rate |
| BAR | Bureau of Automotive Repair |
| BAR | Barrel |
| BAR | Barbados |
| BAR | BRAIN (Broadband Radio Access for IP-based Networks) Access Router |
| BAR | Biblical Archaeology Review |
| BAR | Bay Area Reporter (San Francisco, CA) |
| BAR | Barometer |
| BAR | Baruch (book of the Protestant Apocrypha) |
| BAR | British American Racing (formula 1 racing team) |
| BAR | Burn after Reading (movie) |
| BAR | Bells Are Ringing (musical) |
| BAR | Blade and Rose (gaming guild) |
| BAR | British Archaeological Reports (Archaeopress; UK) |
| BAR | Beyond All Recognition |
| BAR | Black Agenda Radio |
| BAR | Baritone Saxophone |
| BAR | BMDS (Ballistic Missile Defense System) Accountability Report |
| BAR | Bachelor of Arts in Religion (degree; various locations) |
| BAR | Board of Architectural Review (various locations) |
| BAR | British Association of Removers |
| BAR | Bartsow (Amtrak station code; Barstow, CA) |
| BAR | Bachelor of Architecture |
| BAR | Business Analysis Reporting |
| BAR | Bureau of Agricultural Research (Philippines) |
| BAR | Backup and Recovery |
| BAR | British American Racing |
| BAR | Broker Archive |
| BAR | Billing Adjustment Request |
| BAR | Backward Adaptive Re-Encoding |
| BAR | Backbone Access Router |
| BAR | Bandwidth Allocation Request |
| BAR | Backup Archive and Restore (software) |
| BAR | Budget Amendment Request (various organizations) |
| BAR | Base Address Register |
| BAR | British Accreditated Registery (law association) |
| BAR | Billing and Accounts Receivable |
| BAR | Burned Area Rehabilitation (US DOI) |
| BAR | Bangor and Aroostook Railroad |
| BAR | Brigade of the American Revolution |
| BAR | Bureau of Archaeological Research (Florida) |
| BAR | Born Again Rocketeer |
| BAR | Biofragmentable Anastomotic Ring (medical device) |
| BAR | Beta-2-Adrenoceptor |
| BAR | Business Analysis Requirements |
| BAR | Bulk Acoustic Resonator |
| BAR | Bruto Aanvangsrendement (Dutch: Gross Initial Yield) |
| BAR | Broad Area Review |
| BAR | Business Account Representative |
| BAR | Bit Aspect Ratio |
| BAR | Builders All Risk (Insurance) |
| BAR | Buffer Address Register |
| BAR | Bright, Alert and Responsive |
| BAR | British Accreditation Regency |
| BAR | Basins At Risk (freshwater research project) |
| BAR | Blade Area Ratio |
| BAR | Board of Appeals & Review |
| BAR | Beware Alcohol, Run (Alcoholics Anonymous chat slang) |
| BAR | Broadcast Advertisers Reports |
| BAR | Battery Acquisition Radar |
| BAR | Business Analysis Review |
| BAR | Best All-Around Racer |
| BAR | Broadband Aggregation Router (Pannaway Technologies) |
| BAR | Buoyancy Air Releases (SCUBA diving) |
| BAR | Business Area Representative |
| BAR | Bureau of Aeronautics Representative |
| BAR | Bid Analysis Report |
| BAR | Bimonthly Activity Report |
| BAR | Barrett Junction, California (earthquake reporting station) |
| BAR | Brinsley Animal Rescue (Nottingham, UK) |
| BAR | Beep, Alarm, Ring |
| BAR | Business Assurance Reviews |
| BAR | Business Activity Register |
| BAR | Basic Associate Renewal |
| BAR | Backbone Attaching Router |