The meaning of eight ball tattoo is that the final victory belongs to me. The two common ways we play billiards are American free fall and snooker. Snooker is more professional. At least in the billiards hall I saw, it seems that few people play. The hitting order and scoring are more complex, and the ball in snooker has no number. There is a black ball, but there is no number 8 ball.
American free fall bags are divided into real color balls and flower balls. They are distinguished according to the balls of advanced bags. For example, I scored real balls first, so my goal in this game is to score all real balls. However, the black 8 ball does not belong to any kind. It is the last ball. One party can play the black 8 only after scoring all his own balls, and the black 8 ball will win or lose in the end. In addition, there are black 8 ball in American 9 balls, but the rule of 9 balls is that they must hit the ball in 1-9 order, so black 8 ball has no special significance.
Source: @luker_tattoos