per·​fi·​dy ˈpər-fə-dē How to pronounce perfidy (audio)
plural perfidies
: the quality or state of being faithless or disloyal : treachery
: an act or an instance of disloyalty

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. his wife's perfidy was a moment of uncharacteristic weakness
Recent Examples on the Web This violates the prohibition to kill or injure the adversary by resorting to perfidy, Sari said. Ellie Kaufman, ABC News, 30 Jan. 2024 Jim Geraghty has demonstrated the political perfidy in the White House’s approach to debt relief. Noah Rothman, National Review, 9 Oct. 2023 The conventional wisdom about the impact of World War I on the Middle East is that in the wake of the collapse of the Ottoman Empire, European perfidy carved up the region and determined its future. Jonathan Wyrtzen, Foreign Affairs, 28 Feb. 2023 Abraham Lincoln, for instance; World War II in the Pacific; the perfidy of men (as evident in their treatment of women); and so on. Daniel Foster, National Review, 24 Aug. 2023 In the long annals of the republic, the White House has seen its share of perfidy and scandal, presidents who cheated on their wives and cheated the taxpayers, who abused their power and abused the public trust. Peter Baker, New York Times, 2 Aug. 2023 The Iranian mullahs still teach their people about American perfidy by citing the U.S.-backed coup that overthrew Mohammad Mosaddeq in 1953. Max Boot, Foreign Affairs, 10 Mar. 2023 Advertisement In its statement, Fox News demonstrated that not even a court record bulging with evidence of perfidy is enough to shame the organization into genuine contrition. Erik Wemple, Washington Post, 19 Apr. 2023 Andrew Lloyd Webber’s perfidy! New York Times, 11 Dec. 2021 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'perfidy.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

1592, in the meaning defined at sense 1

Time Traveler
The first known use of perfidy was in 1592

Dictionary Entries Near perfidy

Cite this Entry

“Perfidy.” Dictionary, Merriam-Webster, Accessed 23 Feb. 2024.

Kids Definition


per·​fi·​dy ˈpər-fəd-ē How to pronounce perfidy (audio)
plural perfidies
: the quality or state of being faithless or disloyal : treachery

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