| Abbreviation | Definition |
|---|---|
| B | Baseball |
| B | Bingo |
| B | Boxer |
| B | Bronco |
| B4ITC | Bent four in the corner |
| BA | Ball Attach |
| BA | Batting Average |
| BA | Battle Arena |
| BA | Big Arena |
| BAA | Basketball Association of America |
| BAA | Boston Athletic Association |
| BAB | British Aikido Board |
| BABA | Badger Amateur Baseball Association |
| BABA | Baltimore Area Boardsailing Association |
| BABIP | Batting Average on Balls In Play |
| BAC | Beaches Aquatic Club |
| BAC | Bizarre Auction Challenge |
| BAC | Burnsville Athletic Club |
| BACSC | Bay Area Council of Ski Clubs |
| BAD | Bad Anonymous Dicerollers |