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Synonyms and Antonyms of infallible

  1. 1 not being or likely to be wrong <a teacher with an infallible memory for names> Synonyms unerring, unfailing Related Words errorless, faultless, flawless, impeccable; certain, foolproof, inerrant, perfect, sure; dependable, reliable Near Antonyms defective, faulty, flawed, imperfect; undependable, unreliable Antonyms fallible

  2. 2 not likely to fail <an infallible cure for hiccups> 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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