Definitions for bbˈbiˌbi
Random House Webster's College Dictionary
a size of shot, 0.18 in. (0.46 cm) in diameter, fired from an air rifle (BB gun).
Also called BB shot. shot of this size.
Origin of BB:
base on balls.
BB, BB shot(noun)
a small pellet fired from an air rifle or BB gun
A type of pellet which can be shot out of a gun-type "toy"; a ball bearing.