Noun
ten-ball (uncountable)
A form of pool in which players must hit with the cue ball the object ball with the lowest numerical value, and must call the ball to be potted (which may or may not be the object ball initially struck). Any ball apart from the white may be legally potted; whichever player pots the ten ball wins the game (unless it is potted on the break, in which case it is spotted and play continues).
Regardless of the future of the nine-ball versus ten-ball debate, there are already hotly contested professional ten-ball tournaments. Source: Internet