perfidy

noun

ˈpər-fə-dē How to pronounce perfidy (audio)
Definition of perfidynext
1
as in infidelity
lack of faithfulness especially to one's husband or wife his wife's perfidy was a moment of uncharacteristic weakness

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in treachery
the act or fact of violating the trust or confidence of another the full cost—both in compromised intelligence and in human life—of the double agent's perfidy is not yet known

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of perfidy More recently, an al Qaeda operative and suspected mastermind behind the 2000 USS Cole bombing — in which suicide bombers sidled up alongside a US warship, waved to the sailors and then detonated explosives — was charged with perfidy, among other crimes. — Harmeet Kaur, CNN Money, 21 Jan. 2026 The report has raised concerns of perfidy, an act of deception by military forces. — Jenna Prestininzi, Freep.com, 13 Jan. 2026 Ever since, the president and his closest allies haven’t stopped trying to repackage the perfidy as patriotism. — Bloomberg Opinion, Twin Cities, 27 Nov. 2025 The ignorance, the hubris, the lies, the perfidy. — Wesley Stenzel, Entertainment Weekly, 31 Oct. 2025 See All Example Sentences for perfidy
Recent Examples of Synonyms for perfidy
  1. infidelity
  2. treachery
  3. adultery
  4. betrayal
  5. disloyalty
  6. treason
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
  • The killings and his six-week trial in 2023 captivated the true crime world with a mix of treachery, corruption, money, power and Southern accents.
    — Jeffrey Collins, Los Angeles Times, 16 Oct. 2026
  • The killings of Murdaugh’s wife and son and his subsequent six-week trial captivated the true crime world with a mix of treachery, corruption, money, power and Southern accents.
    — ABC News, ABC News, 16 Oct. 2026
Definition of treachery
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
  • 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
Noun
  • When a pair of Israeli filmmakers released a documentary last month about civilian deaths in Gaza, party leaders across the spectrum, including Eisenkot, accused them of treason.
    — Arkansas Online, Arkansas Online, 8 Oct. 2026
  • In 1990, senior West German counterintelligence official Klaus Kuron was ​exposed as a Stasi spy and later convicted of treason.
    — Reuters, NBC news, 7 Oct. 2026
Definition of treason

Browse Nearby Words

perfidiousness
perfidy
perforate
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Cite this Entry

“Perfidy.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/perfidy. Accessed 20 Oct. 2026.

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