Touchback

n. trapping of offensive team in its own goal area (Football)

Definition In American football, a touchback is a ruling which is made and signaled by the referee when the ball crosses into or through the end zone not in control of the team which put it into play. A touchback is not a play, but a result of events that may occur during a play.Kickoffs into the end zone which are fielded but not returned and punts which enter the end zone result in a touchback. Also, a touchback results when a ball carrier fumbles the ball within the field of play and the ball is either not recovered prior to crossing the end line and being out of play or is recovered in the defender's end zone by the defensive team. Additionally, if the defensive team intercepts a forward pass in the defender's end zone, and then makes no effort to return the pass, a touchback is awarded. A forward pass that is thrown through and out of the end zone, however, is not a touchback; it is an incomplete pass.
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Noun
1. (American football) a play in which the opposing team has kicked the football into your end zone
(hypernym) football play
(classification) American football, American football game

(n.)
The act of touching the football down by a player behind his own goal line when it received its last impulse from an opponent; -- distinguished from safety touchdown.