per·​fi·​dy | \ ˈpər-fə-dē How to pronounce perfidy (audio) \
plural perfidies

Definition of perfidy

1 : the quality or state of being faithless or disloyal : treachery
2 : an act or an instance of disloyalty

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Examples of perfidy in a Sentence

A man who built his entire administration upon demanding unctuous loyalty from his allies now finds himself wounded by their shabby betrayal. You'd have to go back to one of Spain's humpbacked Hapsburgs to find court perfidy of the variety that is currently depleting the president's power. — Jack Hitt, Mother Jones, January & February 2006 The petty Robespierres on the public stage appeal to "the real America" to rise up in fury against presidential perfidies; yet in poll after poll the real America keeps telling Washington that it has gone bonkers. — David L. Kirp, Nation, 8 Mar. 1999 I lived there off and on for twenty years, through graduate studies, marriage, the end of marriage, the perfidies of middle age, all the while unaware of passion. — Susan Barron, New England Monthly, October 1989 They are guilty of perfidy. he decided to forgive his wife's perfidy, choosing to ascribe it to a moment of uncharacteristic weakness
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Recent Examples on the Web But Trump is eager to draw attention to Vindman and what Trump perceives as his perfidy. Katherine Doyle, Washington Examiner, "Alexander Vindman to be ousted from National Security Council as early as Friday," 7 Feb. 2020 Stanley Kubrick located a superb film, 1957’s Paths of Glory, in the ornate chambers (and the perfidy) of the generals who oversaw the waste of those lives. Karl Vick, Time, "Sam Mendes on Taking World War I Out of the Trenches and Into the Theater in 1917," 3 Dec. 2019 His descriptions of the perfidy of the British élite have the ring of an insider. Sam Knight, The New Yorker, "How Brexit Will End," 25 Oct. 2019 Her wickedness, unlike his casual and callow perfidy, is rigorously considered. Kyle Smith, National Review, "Confusion’s Masterpiece," 2 Nov. 2019 Saudi and Emirati news channels ran with that version of the story, using it as proof of Turkey and Qatar’s perfidy. Nabih Bulos,, "Libya’s two wars: One on the battlefield and one on Facebook," 17 June 2019 Ultimately, Lydgate succumbs to the jealousy of his rivals and to the perfidy of his patron, while the widowed Dorothea must sacrifice the goal of beneficence for the sake of finding happiness with a new husband. Leslie Lenkowsky, WSJ, "Five Best: Leslie Lenkowsky on Novels About Philanthropy," 7 Dec. 2018 But Iranian hardliners have always opposed it and will argue, with some justice, that their warnings of American perfidy have been borne out. The Economist, "The deal that curtails Iran’s nuclear ambitions seems doomed," 28 Mar. 2018 Anybody who gets Barlow on the phone had better be prepared to talk or trade emails for hours about the nuclear black market, Pakistan's perfidy, his many travails and, now, the nuclear deal with Iran. Jeff Stein, Newsweek, "The Perils of Whistle-Blowing," 4 Dec. 2013

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'perfidy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of perfidy

1592, in the meaning defined at sense 1

History and Etymology for perfidy

Latin perfidia, from perfidus faithless, from per- detrimental to + fides faith — more at per-, faith

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Time Traveler for perfidy

Time Traveler

The first known use of perfidy was in 1592

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Statistics for perfidy

Last Updated

13 Feb 2020

Cite this Entry

“Perfidy.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2020.

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More Definitions for perfidy


How to pronounce perfidy (audio)

English Language Learners Definition of perfidy

literary : the act of betraying someone or something : the state of not being loyal


per·​fi·​dy | \ ˈpər-fə-dē How to pronounce perfidy (audio) \
plural perfidies

Kids Definition of perfidy

More from Merriam-Webster on perfidy

Thesaurus: All synonyms and antonyms for perfidy

Nglish: Translation of perfidy for Spanish Speakers

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