[ trech-uh-ree ]
/ ˈtrɛtʃ ə ri /

noun, plural treach·er·ies.

violation of faith; betrayal of trust; treason.
an act of perfidy, faithlessness, or treason.

Origin of treachery

1175–1225; Middle English trecherie < Middle French, Old French, equivalent to trech(ier) to deceive + -erie -ery

Synonym study

1. See disloyalty. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for treachery

British Dictionary definitions for treachery


/ (ˈtrɛtʃərɪ) /

noun plural -eries

the act or an instance of wilful betrayal
the disposition to betray

Word Origin for treachery

C13: from Old French trecherie, from trechier to cheat; compare trick
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

Word Origin and History for treachery



early 13c., from Old French trecherie "deceit, cheating" (12c.), from trechier "to cheat, deceive" (see trick).

Online Etymology Dictionary, © 2010 Douglas Harper