touchdown n 1: a score in American football; being in possession of the ball across the opponents' goal line 2: a landing (as the wheels touch the landing field); especially of airplanes
Touchdown \Touch"down`\ (t[u^]ch"doun`), n. (Football) The act of touching the football down behind the opponents' goal; also the score (6 points) resulting from such a play. [1913 Webster] {Safety touchdown}. See under {Safety}. [1913 Webster]