perfidy

noun

ˈpər-fə-dē How to pronounce perfidy (audio)
Definition of perfidynext
1
as in infidelity
lack of faithfulness especially to one's husband or wife his wife's perfidy was a moment of uncharacteristic weakness

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in treachery
the act or fact of violating the trust or confidence of another the full cost—both in compromised intelligence and in human life—of the double agent's perfidy is not yet known

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of perfidy 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 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 The ignorance, the hubris, the lies, the perfidy. — Wesley Stenzel, Entertainment Weekly, 31 Oct. 2025 See All Example Sentences for perfidy
Recent Examples of Synonyms for perfidy
  1. infidelity
  2. treachery
  3. adultery
  4. betrayal
  5. disloyalty
  6. treason
Noun
  • Past legal troubles, scrutiny around his finances, allegations of infidelity and a 2023 impeachment.
    — Fort Worth Star-Telegram, Fort Worth Star-Telegram, 4 Nov. 2026
  • Well, The Tailor’s Wife heavily implies The Wicker Baby is the result of The Wicker Husband’s infidelity.
    — Emily Tannenbaum, Glamour, 28 Oct. 2026
Definition of infidelity
Noun
  • The killings and his six-week trial in 2023 captivated the true crime world with a mix of treachery, corruption, money, power and Southern accents.
    — Jeffrey Collins, Los Angeles Times, 16 Oct. 2026
  • The killings of Murdaugh’s wife and son and his subsequent six-week trial captivated the true crime world with a mix of treachery, corruption, money, power and Southern accents.
    — ABC News, ABC News, 16 Oct. 2026
Definition of treachery
Noun
  • The idea shows up in mythology—from Zeus transforming into every kind of animal to commit adultery to Psyche being warned that her new husband, Eros, would be grotesque—as well as in folklore and countless retellings of Beauty and the Beast.
    — Janelle Okwodu, Vogue, 26 Oct. 2026
  • Specifically, Pickard said his understanding of the immunity deal is that his testimony about adultery and an inappropriate relationship cannot be used against him as part of the Uniform Code of Military Justice.
    — Matt Schooley, CBS News, 22 Oct. 2026
Definition of adultery
Noun
  • In the end, though, what gives the film its power is less its visual and aural flair than the deep sense of betrayal at its core.
    — Jim Hemphill, IndieWire, 30 Oct. 2026
  • Netanyahu is already portraying any such alliance as a betrayal of Israel’s Jewish identity and a national security threat, raising the pressure on Eisenkot’s allies, particularly those on the right, to reject it.
    — Tia Goldenberg, Chicago Tribune, 30 Oct. 2026
Definition of betrayal
Noun
  • There’s a sense that doubt would be a form of disloyalty to what came before you, or that admitting a weakness undermines the confidence of the people around you.
    — Flavio Maluf, Forbes.com, 20 Oct. 2026
  • During the government’s response to protests in 2014, Maduro instructed officials to increase the intensity of interrogations involving military personnel suspected of disloyalty, prosecutors say.
    — Antonio María Delgado, Miami Herald, 15 Oct. 2026
Definition of disloyalty
Noun
  • After days of torture, Fawkes named his coconspirators; those who survived capture were executed for treason.
    — Lucia Barnum, Encyclopedia Britannica, 29 Oct. 2026
  • Call it peace or call it treason, call it love or call it reason.
    — Madeline ffitch, Harpers Magazine, 27 Oct. 2026
Definition of treason

Browse Nearby Words

perfidiousness
perfidy
perforate
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Cite this Entry

“Perfidy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/perfidy. Accessed 6 Nov. 2026.

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