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
  • These can range from infidelity and intimidation to aggression and extreme violence.
    — David DeMatteo, The Conversation, 20 Oct. 2026
  • Paxton has faced scrutiny during the campaign for his accumulation of wealth, his past legal troubles, allegations of infidelity, dealings in the attorney general’s office and his 2023 impeachment.
    — Fort Worth Star-Telegram, Fort Worth Star-Telegram, 18 Oct. 2026
Definition of infidelity
Noun
  • Many crimes, including property crimes like burglary or moral sins such as adultery, were punishable by death in the American colonies.
    — Matthew Adams, Fort Worth Star-Telegram, 14 Oct. 2026
  • 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
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
  • 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
  • Anything less will demonstrate societal disloyalty to the government and opposition to the Ukraine War.
    — Regina Smyth, The Conversation, 16 Sep. 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 26 Oct. 2026.

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