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fail-safe

adjective
\ ˈfāl-ˌsāf \

Definition of fail-safe

 (Entry 1 of 2)

1 : incorporating some feature for automatically counteracting the effect of an anticipated possible source of failure
2 : being or relating to a safeguard that prevents continuing on a bombing mission according to a preconceived plan
3 : having no chance of failure : infallibly problem-free the little black dress … has consistently been the fail-safe solution for night — Vogue

fail-safe

noun

Definition of fail-safe (Entry 2 of 2)

: a device or measure that makes something fail-safe

Synonyms & Antonyms for fail-safe

Synonyms: Adjective

can't-miss, certain, infallible, sure, surefire, unfailing

Synonyms: Noun

caution, palladium, precaution, preventive, safeguard

Antonyms: Adjective

fallible

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First Known Use of fail-safe

Adjective

1946, in the meaning defined at sense 1

Noun

1975, in the meaning defined above

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Time Traveler for fail-safe

The first known use of fail-safe was in 1946

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More Definitions for fail-safe

fail-safe

adjective

English Language Learners Definition of fail-safe

: certain not to fail

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Rhyming Dictionary: Words that rhyme with fail-safe

Thesaurus: All synonyms and antonyms for fail-safe

Britannica.com: Encyclopedia article about fail-safe

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