| Name | Meaning | Gender | Origin |
|---|
| Boo | | Unisex | Hebrew |
| Boomer | A large full grown kangaroo. A baby boomer. | Unisex | English |
| Boone | Good | Male | French |
| Boots | | Unisex | Hebrew |
| Boris | Battle, fight | Male | Slavonic |
| Bounce | | Unisex | Hebrew |
| Brady | Descendant of Brádach | Unisex | Gaelic |
| Brandy | Burning wine | Female | English |
| Bronson | Brown's son | Male | English |
| Brownie | Moist chocolate cake with nuts | Unisex | English |
| Bruiser | A large heavyset man | Unisex | English |
| Bruno | Armour | Male | Germanic |
| Brutus | Heavy, slow, foolish | Male | Latin |
| Bubba | | Unisex | Hebrew |
| Buck | He-goat | Male | English |
| Bud | Brother. Nickname Used Since Medieval Times. | Male | English |
| Buddy | Herald | Male | English |
| Bugsy | | Unisex | Hebrew |
| Bull | The adult male of certain large animals like cattle and elephants | Unisex | English |
| Bullet | A metal cylinder shot from a rifle or gun. Used to express speed. | Unisex | English |
| Bullwinkle | | Unisex | Hebrew |
| Burt | Bright | Male | Germanic |
| Buster | One that breaks up something | Unisex | American English |
| Butch | Masculine in appearance or manner. | Unisex | American English |
| Buzz | To move quickly and busily, to bustle | Male | English |
| Byron | At the cattle sheds | Male | English |
| Caesar | Long Hair | Male | Latin |
| Cairo | Victorious one | Unisex | Arabic |
| Calvin | Bald | Male | French |
| Cannon | Canon | Male | English |