Willful betrayal of fidelity, confidence, or trust; perfidy.(noun)
The act or an instance of such betrayal.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "treachery" in a sentence
"This determined man, whose experience in the East Indies was of long date, and who had already served as director-general, came into his new office with an intense prejudice against the English, and with a firm resolve to put an end to what he described as their treachery and intrigues."
"In this condition the legions burst in on them, furious at what they called the treachery of the previous day, and merciless in their vengeance."
"Fink grumbled, and Anton could not forget what he called treachery to Bernhard; and so it was, that for some weeks they no longer spent their evenings together."