perfidy

noun

per·​fi·​dy ˈpər-fə-dē How to pronounce perfidy (audio)
plural perfidies
Synonyms of perfidynext
1
: the quality or state of being faithless or disloyal : treachery
2
: 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
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.
Any time there is a crisis in Iran, the 1953 British-American coup against Prime Minister Mohammad Mossadegh is dusted off as Exhibit A in the case against Western perfidy. Bobby Ghosh, Time, 5 Mar. 2026 But the mayor’s dramatic tale of his predecessor’s fiscal fiddling was designed with a clear political agenda in mind: both to underline the magnitude of the problem and to identify the villains responsible for this perfidy. Washington Post, 29 Jan. 2026 More recently, an al Qaeda operative and suspected mastermind behind the 2000 USS Cole bombing — in which suicide bombers sidled up alongside a US warship, waved to the sailors and then detonated explosives — was charged with perfidy, among other crimes. Harmeet Kaur, CNN Money, 21 Jan. 2026 The report has raised concerns of perfidy, an act of deception by military forces. Jenna Prestininzi, Freep.com, 13 Jan. 2026 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

Cite this Entry

“Perfidy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perfidy. Accessed 10 Mar. 2026.

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

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