perfidious

adjective per·fid·i·ous \ (ˌ)pər-ˈfi-dē-əs \

|Updated on: 21 May 2018

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Examples: perfidious in a Sentence

Editor's Note: Did You Know?

Definition of perfidious

: of, relating to, or characterized by perfidy

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perfidiously

adverb

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perfidiousness

noun

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Examples of perfidious in a Sentence

We were betrayed by a perfidious ally.
a perfidious campaign worker revealed the senator's strategy to his leading rival for the nomination

Recent Examples of perfidious from the Web

The new heroes are black and white women determined to clean up the mess created by Fowler and his perfidious white financial backer.

— tony adler, Chicago Reader, "There’s a great play to be written about bigotry in Evanston in the early 20th century," 11 May 2018
Some have warned of a perfidious plot to revive the British empire with help from Muslims, particularly Shias, who revere the Prophet’s descendants.

— The Economist, "Muslims consider Queen Elizabeth’s ties to the Prophet Muhammad," 5 Apr. 2018
This ought to be the primary context for any analysis of Trump’s standoff with the FBI, but instead Dershowitz wishes it away, and reimagines Trump as an innocent man hounded by a perfidious and unethical prosecutor.

— jonathan chait, Daily Intelligencer, "Alan Dershowitz’s Audition to Be Trump’s Lawyer Is Not Going Well," 21 Mar. 2018
The problem isn’t that Obama and Clinton and Trump and whoever else are all perfidious backstabbers who have betrayed the anti-intervention movement.

— noah berlatsky, Slate Magazine, "We Need a War Tax," 24 Apr. 2017
Their allegiance was met by this unholy alliance of perfidious greed devolving rapidly into the audacity of vituperative unparalleled predatory rapacity.

— Fortune, "24 Facts You May Not Know About Warren Buffett," 31 Aug. 2017
Unsurprisingly, many ordinary Americans came to see themselves as victims of perfidious conspiracies, channeling their energies into indignant rebellions like the Anti-Masonic Party.

— kevin baker, New Republic, "Trail of Fears," 13 June 2017
Even by that relatively late date, when the authoritarian nature of the regime was already clear, Jacobin was defending it against its perfidious neoliberal critics.

— jonathan chait, Daily Intelligencer, "100 Years After the Bolshevik Revolution, Communism Hasn’t Changed," 28 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'perfidious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Did You Know?

We wouldn't lie to you about the history of "perfidious" - even though the word itself suggests deceitfulness. The modern English meaning of "perfidious" remains faithful to that of its Latin ancestor, perfidus, which means "faithless." English speakers have used "perfidious" to mean "treacherous" since at least 1572. One of the earliest known uses of the term can be found in Act V, scene iii of Shakespeare’s All's Well That Ends Well: the "perfidious slave" Parolles is thought to be an unreliable witness; he’ll say whatever suits his purpose, whether true or not. In contemporary usage, "perfidious" not only implies treacherousness, but an inability to be reliable or honorable.

First Known Use of perfidious

1572

in the meaning defined above

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perfidious Synonyms

Synonym Discussion of perfidious

faithless, false, disloyal, traitorous, treacherous, perfidious mean untrue to what should command one's fidelity or allegiance. faithless applies to any failure to keep a promise or pledge or any breach of allegiance or loyalty.