treachery

noun

treach·​ery ˈtre-chə-rē 

ˈtrech-rē

plural treacheries

1

: violation of allegiance or of faith and confidence : treason

2

: an act of perfidy or treason

Synonyms

• backstabbing
• betrayal
• business
• disloyalty
• double cross
• faithlessness
• falseness
• falsity
• infidelity
• perfidy
• sellout
• treason
• two-timing
• unfaithfulness

Examples of treachery in a Sentence

a tale of treachery and revenge

was furious that she revealed his secret and never forgave her for the treachery

Recent Examples on the Web

After a season of treachery and deception, the winner or winners of The Traitors UK Season 3 have been revealed. —Armando Tinoco, Deadline, 24 Jan. 2025

This would be immediately followed by my dad standing up, racing over to my uncle, and sometimes grabbing him by the collar to stop him from completing an action that in their eyes seemed to be an act of utter betrayal and treachery. —Wayne Chan, San Diego Union-Tribune, 21 Jan. 2025

Welcome back for another season full of [Alan Cumming voice] deception, backstabbing and treachery! —Nick Caruso, TVLine, 9 Jan. 2025

Yet Milady and her treachery have for nearly 200 years always stood out. —Stephen Schaefer, Boston Herald, 15 Apr. 2024

Word History

Etymology

Middle English trecherie, from Anglo-French, from trecher, tricher to deceive, from Vulgar Latin *triccare — more at trick entry 1

First Known Use

13th century, in the meaning defined at sense 1

Kids Definition

treachery

noun

treach·​ery ˈtrech-(ə-)rē 

plural treacheries

1

: violation of allegiance or of faith and confidence : treason

2

: an act of treason