Definition of perfidious in English:

perfidious

adjective

literary
  • Deceitful and untrustworthy.

    ‘a perfidious lover’
    • ‘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.’
    • ‘She is indifferent, negligent, unfeeling, untrustworthy, and perfidious.’
    • ‘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.’
    • ‘‘Albion has never seemed so perfidious or so lucky,’ the article begins.’
    • ‘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.’
    treacherous, duplicitous, deceitful, disloyal, faithless, unfaithful, traitorous, treasonous, false, untrue, double-dealing, dishonest, two-faced, janus-faced, untrustworthy
    View synonyms

Origin

Late 16th century: from Latin perfidiosus, from perfidia ‘treachery’.

Pronunciation

perfidious

/pəˈfɪdɪəs/