treach·​er·​ous | \ ˈtre-chə-rəs How to pronounce treacherous (audio) , ˈtrech-rəs \

Definition of treacherous

1a : likely to betray trust : unreliable a treacherous memory
b : providing insecure footing or support treacherous quicksand
c : marked by hidden dangers, hazards, or perils
2 : characterized by or manifesting treachery : perfidious

Other Words from treacherous

treacherously adverb
treacherousness noun

Choose the Right Synonym for treacherous

faithless, false, disloyal, traitorous, treacherous, perfidious mean untrue to what should command one's fidelity or allegiance. faithless applies to any failure to keep a promise or pledge or any breach of allegiance or loyalty. faithless allies false stresses the fact of failing to be true in any manner ranging from fickleness to cold treachery. betrayed by false friends disloyal implies a lack of complete faithfulness to a friend, cause, leader, or country. disloyal to their country traitorous implies either actual treason or a serious betrayal of trust. traitorous acts punishable by death treacherous implies readiness to betray trust or confidence. a treacherous adviser perfidious adds to faithless the implication of an incapacity for fidelity or reliability. a perfidious double-crosser

Examples of treacherous in a Sentence

a treacherous act of betrayal They were not prepared to hike over such treacherous terrain. The snow made their hike all the more treacherous. Discussions about money can lead couples into treacherous territory.
Recent Examples on the Web The illicit drug market continues to become more treacherous. Jim Crotty, STAT, 7 Aug. 2022 The weather in Washington, D.C., was treacherous Thursday evening, when four people were struck by lightning outside the White House. Travis Andersen,, 5 Aug. 2022 Negotiating the release of basketball star Brittney Griner could be treacherous territory for the Biden administration. Rick Klein, ABC News, 5 Aug. 2022 Jean-Marc Peillex, mayor of Saint-Gervias-les-Bains, a town on the French side, says too many unqualified climbers are gambling with their lives on the mountain, where recent hot weather has made conditions more treacherous. CNN, 4 Aug. 2022 Cantlay gets up-and-down to save par around the treacherous 18th green to shoot 66. Kirkland Crawford, Detroit Free Press, 30 July 2022 Long before much of the world rallied to Ukraine’s aid, the country was a treacherous place to do business. Anna Hirtenstein, WSJ, 28 July 2022 The platforms—which have a treacherous 6 inch heel—could have been lifted straight out of the Aughts wardrobe of J. Hayley Maitland, Vogue, 25 July 2022 YouTube/Lionsgate Ian McShane is back as the treacherous Winston. Jennifer Ouellette, Ars Technica, 23 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'treacherous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of treacherous

14th century, in the meaning defined at sense 2

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The first known use of treacherous was in the 14th century

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Last Updated

14 Aug 2022

Cite this Entry

“Treacherous.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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More Definitions for treacherous


treach·​er·​ous | \ ˈtre-chə-rəs How to pronounce treacherous (audio) \

Kids Definition of treacherous

1 : not safe because of hidden dangers This was a treacherous road at night …— John Reynolds Gardiner, Stone Fox
2 : not trustworthy : guilty of betrayal or likely to betray a treacherous enemy

Other Words from treacherous

treacherously adverb

More from Merriam-Webster on treacherous

Nglish: Translation of treacherous for Spanish Speakers

Britannica English: Translation of treacherous for Arabic Speakers


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