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Synonyms

treachery

American  
[trech-uh-ree] / ˈtrɛtʃ ə ri /

noun

  • treacheries
    plural
  1. violation of faith; betrayal of trust; treason.

    Antonyms:
    loyalty
  2. an act of perfidy, faithlessness, or treason.


treachery British  
/ ˈtrɛtʃərɪ /

noun

  1. the act or an instance of wilful betrayal

  2. the disposition to betray

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

See disloyalty.

Other Word Forms

Noun Inflected Forms

Etymology

Origin of treachery

First recorded in 1175–1225; Middle English trecherie, from Middle French, Old French, from trech(ier) “to deceive” ( see trick) + -erie -ery

Explanation

Treachery is trickery, cheating, and deceit, like the treachery of your former friend who only stuck around until he stole your girlfriend and turned the whole grade against you. The noun treachery comes from the Old French word trechier, “to cheat.” Many a corrupt government or dictator has been accused of treachery: deceiving the people and abusing their trust. Greed is a common cause of treachery — with the promise of wealth, people can be tempted to betray their country and even their loved ones, as new celebrities find out when their best friends sell embarrassing secrets to the tabloids.

Keep Reading on Vocabulary.com

Vocabulary lists containing treachery

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Most of the unhappy denizens of Dante’s imagined hell are being eternally tormented for specific moral crimes in categories covering lust, gluttony, greed, anger, heresy, violence, fraud and treachery.

From Salon Mar. 8, 2026

It’s a sprawling tale of divine corruption and human treachery that ends with the world being purified by fire and flood.

From The Wall Street Journal Feb. 12, 2026

His treachery began in 1985 when he gave the Soviets the names of a few KGB officers secretly working for the FBI in exchange for $50,000.

From BBC Jan. 6, 2026

Lizza, in his own statement, said: “Telling the truth is not harassment and accountability is not an ax, though I understand why Olivia finds it unpleasant to be confronted with her treachery and betrayal.”

From The Wall Street Journal Dec. 4, 2025

They parted, she to the palace to weep over her treachery to her father, he to the ship to send two of his comrades for the dragon’s teeth.

From "Mythology: Timeless Tales of Gods and Heroes" by Edith Hamilton

Le Pen alliances are famously rocky, and the family’s treacheries have for decades delighted the French media.

From New York Times Mar. 31, 2022

“There are treacheries and enmities in abundance against me. Joan Sumner is now claiming she never agreed to marry me. She complains that I have claimed to be richer than I am.”

From New York Times Sep. 8, 2016

Conrad’s bleak treacheries and Buchan’s sour anomie became grist to le Carré’s genius.

From The Guardian Oct. 17, 2015

Along the eastern shore of Nantucket, exposed to the delights and treacheries of the Atlantic, lies Sankaty Head.

From Golf Digest Nov. 3, 2014

His choice had been to stay in the deep dark water far out beyond all snares and traps and treacheries.

From "The Old Man and The Sea" by Ernest Hemingway

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