per·​fi·​dy | \ ˈpər-fə-dē \
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

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 Shock has turned to a national shunning as America finds unity in President Trump's perfidy. Fox News, "Gutfeld: The media need to focus on reality instead of fear," 21 July 2018 The whole purpose of Trump’s Supreme Court selection process has been to eliminate the possibility of nominating someone who might commit Kennedy’s perfidies of moderation. Jeffrey Toobin, The New Yorker, "How Trump’s Supreme Court Pick Could Undo Kennedy’s Legacy," 9 July 2017 No rumor of black perfidy was too outlandish to be believed. Joseph Crespino, WSJ, "‘Deep South Dispatch’ Review: Witness to the Persecution," 10 July 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 Getting to the bottom of Russia’s perfidy is a goal every American should support, just as possible abuse of the government’s surveillance powers ought to concern everyone, regardless of party or ideology. Andrew C. Mccarthy, National Review, "‘Delegitimizing’ Mueller? Don’t Blame the Nunes Memo," 7 Feb. 2018 Within minutes, pundits at Emirati and Saudi television stations were expounding on the perfidy of Qatar and issuing heated denunciations. Declan Walsh, New York Times, "Tiny, Wealthy Qatar Goes Its Own Way, and Pays for It," 22 Jan. 2018

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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Statistics for perfidy

Last Updated

2 Jan 2019

Look-up Popularity

Time Traveler for perfidy

The first known use of perfidy was in 1592

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More Definitions for perfidy



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 \
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

Comments on perfidy

What made you want to look up perfidy? Please tell us where you read or heard it (including the quote, if possible).


a servile follower or underling

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