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
  • The same day Diana wore the gown, her estranged husband admitted to infidelity on national television.
    — Bailey Bujnosek, InStyle, 9 July 2026
  • Plots tend to involve women in various types of distress, facing things like murder, stalking, infidelity, illicit love, kidnapping, and storm-chasing serial killers.
    — Brianna Zigler, Entertainment Weekly, 7 July 2026
Definition of infidelity
Noun
  • Hundreds of pages of filings in a civil lawsuit and countersuit detail allegations of fraud and elder abuse, years of adultery, and a battle for property, luxury sports cars and cash.
    — Amber Gaudet, Charlotte Observer, 10 July 2026
  • In addition to being accused of adultery by his estranged wife, Paxton, a staunch MAGA ally, has faced felony securities fraud charges, an FBI investigation into corruption and state impeachment hearings that ended in an acquittal.
    — Meredith Kile, PEOPLE, 7 July 2026
Definition of adultery
Noun
  • Ultimately, the reassurances about community resources and air quality failed to quell the fury inside the room as residents took the microphone during the Q&A section and repeatedly expressed feelings of betrayal and mistrust.
    — Clara Harter, Los Angeles Times, 10 July 2026
  • Cupertino, which is slated to premiere in the fall on CBS, follows a former tech lawyer (Colter) who, after experiencing a betrayal from his former employer, teams up with another attorney to represent underdogs in litigation against tech giants.
    — Katie Kilkenny, HollywoodReporter, 10 July 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
  • And still, some people insist that admitting the flaws in our history — and our present — constitutes an act of innate disloyalty.
    — Orlando Sentinel Editorial Board, The Orlando Sentinel, 28 June 2026
  • Treating rumors as diagnostic signals of uncertainty or weak trust, rather than disloyalty, helps leaders improve communication and align words with observable actions.
    — Benjamin Laker, Forbes.com, 19 June 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 17 Jul. 2026.

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