BACKSTOP

I. noun Date: 1851 something at the back serving as a stop: as, a screen or fence for keeping a ball from leaving the field of play, a stop (as a pawl) that prevents a backward movement (as of a wheel), a player (as the catcher) positioned behind the batter, II. transitive verb Date: 1941 support , bolster , to serve as a ~ to, to play the position of goalkeeper for