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\ 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
nounDefinition of fail-safe (Entry 2 of 2)
: a device or measure that makes something fail-safe
Synonyms & Antonyms for fail-safe
Synonyms: Adjective
Synonyms: Noun
Antonyms: Adjective
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More Definitions for fail-safe
fail-safe
adjectiveEnglish Language Learners Definition of fail-safe
: certain not to fail
See the full definition for fail-safe in the English Language Learners Dictionary
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Time Traveler for fail-safe
The first known use of fail-safe was in 1946
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