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 Rules affecting retirement withdrawals were treacherous and confusing even before the coronavirus hit, and recent legislation has changed several key provisions, at least temporarily. Russ Wiles, The Arizona Republic, "Pay attention to these key tax changes caused by coronavirus pandemic," 29 June 2020 According to The Hollywood Reporter, the untitled Disney project will star Robbie as a unique hero on her own journey across the treacherous seas — separate from the storyline of Depp's pirate captain. Ineye Komonibo,, "Margot Robbie To Star In The Next Pirates Of The Caribbean Film," 27 June 2020 Consider how our gun culture makes American society needlessly treacherous, for police and citizens alike. Firmin Debrabander, The New Republic, "America’s Cop Problem Is Also a Gun Problem," 24 June 2020 Part of self-sufficiency means using the right tools for the job, and being prepared to tackle treacherous conditions. Outdoor Life, "How to Take Your First Overland Hunting Adventure this Fall," 15 June 2020 And, as coronavirus cases spike in Oregon, the path ahead continues to look treacherous. oregonlive, "Why Sally Kipyego is in Kenya, English Gardner is speaking out and Phil Knight is being honored: Oregon track & field rundown," 14 June 2020 The mission to rescue a kidnapped scientist turns out to be far more treacherous than expected, leading Bond onto the trail of a mysterious villain armed with dangerous new technology. Clark Collis,, "No Time to Die release date moved up," 13 June 2020 This is both a treacherous time and a time of great promise. Claudia Wallis, Scientific American, "Why Racism, Not Race, Is a Risk Factor for Dying of COVID-19," 12 June 2020 Shift workers in economically treacherous situations are forced to risk their health for a paycheck. Jeffrey Geller, STAT, "In the face of Covid-19, the U.S. needs to change how it deals with mental illness," 29 May 2020

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

Time Traveler

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

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Statistics for treacherous

Last Updated

8 Jul 2020

Cite this Entry

“Treacherous.” Dictionary, Merriam-Webster, Accessed 8 Jul. 2020.

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More Definitions for treacherous


How to pronounce treacherous (audio)

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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