fail–safe

adjective

Synonyms and Antonyms of FAIL-SAFE

not likely to fail <men have traditionally regarded flowers as the fail-safe gift for Valentine's Day>

Synonyms can't-miss, certain, fail-safe, sure, surefire, unfailing

Related Words dependable, reliable; deadly, unerring

Near Antonyms doubtful, questionable, uncertain

Antonyms fallible

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