Backstop - Definition
backstop
n 1: (baseball) the person who plays the position of catcher
[syn: catcher, backstop]
2: (baseball) a fence or screen (as behind home plate) to
prevent the ball from traveling out of the playing field
3: a precaution in case of an emergency; "he acted as a backstop
in case anything went wrong"
v 1: act as a backstop