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Webster 1913 Edition

(tŭch′băkˊ)

Noun.

(Football)

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.

touchback ‎(plural touchbacks)

(American football) The result of a play (usually a kickoff or punt) in which the ball passes out the back of the end zone or a team otherwise gains possession of the ball in their own end zone.
The ball sailed into the end zone for a touchback and the Eagles had possession on the 20-yard line.