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
  • Many commenters highlight fears of infidelity, health risks, and the belief that a bisexual man might eventually prefer men, leading to heartbreak.
    — Razzan Nakhlawi, Washington Post, 10 Oct. 2026
  • But their relationship cracked amid Hill’s infidelity and a lack of trust, Vaccaro testified.
    — Milena Malaver, Miami Herald, 7 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
  • In this painful experience, one is exposed (the betrayal that is blushing) and longs to hide oneself.
    — Eugenie Brinkema, ARTnews.com, 17 Oct. 2026
  • Someone to blame Burns knows the cost of Salem’s betrayals about as well as anyone.
    — Jennifer Byrne, Popular Science, 15 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 20 Oct. 2026.

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