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
  • Defense attorney Emily Smith argued the prosecution’s case lacked key evidence, including the murder weapon, and had little to stand on aside from his infidelity.
    — Nicki Brown, CNN Money, 29 Sep. 2026
  • By the end of Volume I, the court romance has devolved into a series of infidelities, both personal and political, which cause the corruption and destabilization of England’s fledgling democracy.
    — Eileen Hunt, Fortune, 28 Sep. 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.

Browse Nearby Words

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 6 Oct. 2026.

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