perfidiousness

noun

Definition of perfidiousnessnext
as in infidelity
lack of faithfulness especially to one's husband or wife perfidiousness eventually led to the couple's divorce

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Recent Examples of Synonyms for perfidiousness
  1. infidelity
  2. adultery
  3. betrayal
  4. perfidy
  5. disloyalty
Noun
  • What readers are saying The comments on the article discuss various aspects of financial infidelity and its impact on relationships.
    — Jenna Ryu, Washington Post, 23 Oct. 2026
  • The podcast’s indefinite hiatus comes shortly after Hila accused her husband of infidelity on her own Instagram account late Thursday night.
    — Andrea Flores, Los Angeles Times, 23 Oct. 2026
Definition of infidelity
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
  • The boldest declarations of solidarity, Lee knows, often precede the quietest and cruellest of betrayals.
    — Justin Chang, New Yorker, 23 Oct. 2026
  • Secretly draining shared savings or hiding major debt are obvious betrayals.
    — Jenna Ryu, Washington Post, 23 Oct. 2026
Definition of betrayal
Noun
  • Platner, indeed, has boiled down nearly all political problems to the perfidy of sinister oligarchs.
    — Jonathan Chait, The Atlantic, 6 July 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, Encyclopedia Britannica, 14 May 2026
Definition of perfidy
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
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.

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perfidious
perfidiousness
perfidy
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Cite this Entry

“Perfidiousness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/perfidiousness. Accessed 28 Oct. 2026.

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