Definition of perfidious in English:



  • Deceitful and untrustworthy.

    ‘a perfidious lover’
    • ‘The cause of these antinomies is language, for language, being a useful tool, is also a self-locking instrument - and at the same time a perfidious one, since it tells nothing about when it becomes a pitfall itself.’
    • ‘‘Albion has never seemed so perfidious or so lucky,’ the article begins.’
    • ‘She is indifferent, negligent, unfeeling, untrustworthy, and perfidious.’
    • ‘I refer, of course, not to the evil, perfidious nature of corporate governance because, let's face it, we're all too cowed and defenceless to complain, but to badly dubbed television commercials.’
    • ‘If anyone in history has ever emitted a bigger pile of oozing, sanctimonious, unctuous, fetid, perfidious, malodorous offal than this, I'd like to know what it could possibly be.’
    treacherous, duplicitous, deceitful, disloyal, faithless, unfaithful, traitorous, treasonous, false, untrue, double-dealing, dishonest, two-faced, janus-faced, untrustworthy
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Late 16th century: from Latin perfidiosus, from perfidia ‘treachery’.