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"backstop" is also used as a crossword clue. If that's what you saw, the answer is often catcher (7 letters).
Definitions
a precaution in case of an emergency
Word origin
From back + stop.
Used in a sentence
“Irish prime minister Leo Varadkar, this morning, said a time-limited backstop would be unacceptable, and has previously promised to vote down the UK’s Brexit withdrawal deal unless it features a satisfactory backstop.”
“[…] to be set up in Indonesia with a phony book and school supplies company established in New York City as a backstop.”
“Closely representing an alibi, creating a backstop could involve such measures as having people available to verify the details of an agent's cover story.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Emergency safeguard”8 letters
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