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
  • Sure, that sounds ridiculous for a season about rape, infidelity, mass murder, suicide, and society’s ruthless commodification of those very things.
    — Alison Foreman, IndieWire, 6 Oct. 2026
  • The 82-year-old actor writes candidly about infidelity, addiction, his son’s imprisonment and his battle with oral cancer, while reflecting on the costs of a life in show business and his love for California.
    — Maddie Connors, Los Angeles Times, 5 Oct. 2026
Definition of infidelity
Noun
  • The Royal Family, whose relations with Spencer have long been strained, are said to fear the book could contain numerous bombshells about Charles and Diana’s relationship, which was infamously plagued by adultery and acrimony.
    — K.J. Yossman, Variety, 17 Sep. 2026
  • Its citizens held slaves, some of whom were shackled for committing adultery.
    — Boris Kachka, The Atlantic, 4 Sep. 2026
Definition of adultery
Noun
  • Washington’s track record, after all, is defined by betrayal.
    — Mohammad Ayatollahi Tabaar, Foreign Affairs, 1 Oct. 2026
  • Pulled into the action is Liz Gold, an idealistic young woman whose courage and conviction force Leamas to navigate a world where loyalties fracture and betrayal is inevitable.
    — Max Goldbart, Deadline, 28 Sep. 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
  • Anything less will demonstrate societal disloyalty to the government and opposition to the Ukraine War.
    — Regina Smyth, The Conversation, 16 Sep. 2026
  • Leaders can maintain alumni relationships, make re-entry culturally acceptable and ensure hiring processes do not automatically treat departure as disloyalty.
    — Sheila Callaham, Forbes.com, 29 Aug. 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 9 Oct. 2026.

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