perfidy

noun

per·​fi·​dy ˈpər-fə-dē How to pronounce perfidy (audio)
plural perfidies
Synonyms of perfidy
1
: the quality or state of being faithless or disloyal : treachery
2
: an act or an instance of disloyalty

Synonyms of perfidy

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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. his wife's perfidy was a moment of uncharacteristic weakness
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The ignorance, the hubris, the lies, the perfidy. — Wesley Stenzel, Entertainment Weekly, 31 Oct. 2025 The report has raised concerns of perfidy, an act of deception by military forces. — Jenna Prestininzi, Freep.com, 13 Jan. 2026 If the landing had been faked, the Soviets would have figured it out and would have loved to reveal to the world America’s perfidy. — Encyclopedia Britannica, 14 May 2026 Ever since, the president and his closest allies haven’t stopped trying to repackage the perfidy as patriotism. — Bloomberg Opinion, Twin Cities, 27 Nov. 2025 See All Example Sentences for perfidy

Word History

Etymology

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

Browse Nearby Words

perfidiousness
perfidy
perfilograph
See all Nearby Words

Cite this Entry

“Perfidy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perfidy. Accessed 8 Jul. 2026.

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Kids Definition

perfidy

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

More from Merriam-Webster on perfidy

Nglish: Translation of perfidy for Spanish Speakers

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