English▸ noun
1 a person or thing placed at the rear of or behind something as a barrier, support, or reinforcement:
bullets volleyed into the backstop of a flood-control canal.
▪ an emergency precaution or last resort:
the human operator has to act as the ultimate backstop when things go badly wrong.
2 Baseball a high fence or similar structure behind the home plate area.
▪ a catcher:
he tore the chest protector completely off the big Yankee backstop.