touchback

In American football, a touchback is a ruling which is made and signaled by an official when the ball becomes dead on or behind a team's own goal line (i.e., in an end zone) and the opposing team gave the ball the momentum, or impetus, to travel over or across the goal line. Such impetus may be imparted by a kick, pass, fumble, or in certain instances by batting the ball. A touchback is not a play, but a result of events that may occur during a play. A touchback is the opposite of a safety with regard to impetus since a safety is scored when the defending team is responsible for the ball becoming dead on or behind its own goal line.