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 of treachery

• betrayal
• treason

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

Guides spoke of the monthlong siege that ended only because of the treachery of a local noble who turned on the sultan and allowed British troops to scale the walls. — Ishaan Tharoor, New Yorker, 2 July 2026

This is not treachery but the truest and noblest affection. — Ann Manov, Harpers Magazine, 23 June 2026

Peacock’s adventures in treachery The Traitors was the top dog, scoring five prizes including Best Competition Series and Best Host for Alan Cumming. — Erik Pedersen, Deadline, 3 June 2026

Upon learning of Ava’s treachery, Deborah HOWLS. — Jessica M. Goldstein, Vulture, 1 May 2026

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

Rhymes for treachery

• lechery

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