Definition of perfidy in English:

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Pronunciation: /ˈpərfədē/


Deceitfulness; untrustworthiness.
Example sentences
  • I have been accused of perfidy, malingering, duplicity, charlatanism and forty other words that I don't know the meaning of.
  • Think of the valiant whistleblower inside a corporation or an agency who puts himself at risk to uncover criminal perfidy.
  • With possible political perfidy such a hot topic at Westminster, it is with perfect timing that the Lyceum and Citizens' theatres bring two of England's great plays of history and politics to the stage.
treachery, duplicity, deceit, deceitfulness, disloyalty, infidelity, faithlessness, unfaithfulness, betrayal, treason, double-dealing, untrustworthiness, breach of trust
literary perfidiousness


Late 16th century: via French from Latin perfidia, from perfidus 'treacherous', based on per- 'to ill effect' + fides 'faith'.

  • This literary word for ‘deceitfulness’ came via French from Latin perfidia ‘treachery’, from perfidus ‘treacherous’, based on per- ‘to ill effect’ and fides ‘faith’. The adjective perfidious dates from the same period. The expression perfidious albion is a translation of the French perfide Albion; the phrase appears to have been first used by the Marquis de Ximenès (1726–1817) with reference to the British joining the allies who were already fighting France in 1793, but was popularized during a recruitment campaign under Napoleon I in 1813. It was adopted into German (in its French form) during the early 19th century and had become naturalized by the time of Bismarck. It was used in German anti-British propaganda during the First World War (1914–18), and during the Second World War (1939–45) to undermine French trust in Britain as an ally.

For editors and proofreaders

Syllabification: per·fi·dy

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