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

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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.
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Recent Examples on the Web Travel has already become treacherous in some places and is expected to worsen through the day with ice accumulations possibly leading to power outages as utility lines become weighed down. Leada Gore |, al, 15 Feb. 2021 Even with a tiny amount of freezing rain, roads can become treacherous. Dave Epsein,, 14 Feb. 2021 Alex Conant, a Republican strategist and former aide to Senator Marco Rubio of Florida, said that the Trump campaign was entering a dangerous period, one when a campaign heading for a possible defeat can become treacherous. Maggie Haberman, New York Times, 8 Oct. 2020 Due to the treacherous nature of the climb, things move very slowly, as folks do their best to advance up the rock without tumbling into the valley below. Alex Schechter, Travel + Leisure, 1 June 2021 So, which Class 4A section looks like the most treacherous to traverse? Jim Paulsen, Star Tribune, 31 May 2021 The Marian portions rove from Montana to Manhattan to Scotland and Antarctica, and read like a carnival of early 20th century American history, packed with bootleggers, treacherous boxcar rides, and tragic shipwrecks. Vogue, 29 May 2021 This treacherous policy terrain had been undermining presidencies for decades, Biden argued, and Obama shouldn’t jeopardize his time in office so soon. Washington Post, 30 Apr. 2021 With treacherous terrain, how exactly do firefighters work in the mountains? Jay R. Jordan, Chron, 15 Apr. 2021

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.

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First Known Use of treacherous

14th century, in the meaning defined at sense 2

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Time Traveler for treacherous

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

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Statistics for treacherous

Last Updated

15 Jun 2021

Cite this Entry

“Treacherous.” Dictionary, Merriam-Webster, Accessed 21 Jun. 2021.

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More Definitions for treacherous



English Language Learners Definition of treacherous

: not able to be trusted : showing that someone cannot be trusted
: very dangerous and difficult to deal with


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


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