To determine the order of play in billiards by successively hitting the cue ball against the end rail, the ball rebounding closest to the head rail indicating the player to shoot first.

• （以击母球的方式）决定先后次序一种决定台球比赛顺序的方法，即在成功地击中母球底边并使其从台球桌底边上弹回后，以最靠近顶边的球的击打者为先击者