A solid black [[billiard ball]], the only one of this color in a standard 15-ball set composed of differently colored solid and striped balls. This ball is so distinct that it has lent its name to an entire billiards game (eight-ball, where the object is to shoot into pockets balls of one type before doing the same on the 8-ball last) and has transcended outside the context of billiards into popular culture at large. An oversized decision-making/fortune-telling device based on it called the Magic 8-Ball was invented in 1946 by Albert C. Carter and Abe Bookman and is currently manufactured by Mattel.
8-ball