treach·er·ous | \ˈtre-chə-rəs, 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

Thai Prime Minister Prayut Chan-ocha visited one of the hospitals treating the boys on Tuesday, and told the press that the team members had been given anti-anxiety medication before undertaking the long, treacherous journey to freedom. Madeleine Aggeler, The Cut, "All 12 Thai Soccer Players and Their Coach Have Been Rescued," 10 July 2018 One by one, the first four to be rescued emerged after a treacherous, hourslong journey through the tight, underwater passageways of Tham Luang Cave. New York Times, "In Daring Underwater Cave Rescue, 4 of 13 Thai Are Freed," 8 July 2018 That the first fatality of the fraught mission was an experienced diver underscored the dangers of the plan to extract the group through the treacherous waterways. Time, "Divers Begin Rescue Operation to Free 12 Boys and Their Soccer Coach Trapped in a Thai Cave," 8 July 2018 No one should subject their child to this treacherous journey. Salvador Rizzo, Washington Post, "Recidivism Watch: Trump administration again blames others for its own family separation policy," 14 June 2018 Besides enduring treacherous journeys to America’s farms and slaughterhouses, foreign workers are also subjected to atrocious working conditions, suffering in secret. Gene Baur, Fortune, "Immigrant Farm Workers Endure Inhumane Conditions. Here’s What We Can Do," 8 June 2018 As a result, people are skipping official ports of entry and crossing over unofficially -- sometimes going through treacherous journeys to do so. Madison Park, CNN, "'No free ticket' Canada warns as Nigerian asylum seekers cross from US," 9 May 2018 The chief storyteller is a woman, giving the audience the female perspective of the treacherous journey. Joan Rusek,, "Fairmount art center names Fleming-Gifford to top post: Valley Views," 13 Feb. 2018 Conditions on the mountain were treacherous in the middle of the hot summer day, with rocks falling and ice melting. CBS News, "Man rescued from Mount Hood after climbing it to kill himself, authorities say," 13 July 2018

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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Last Updated

3 Oct 2018

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Time Traveler for treacherous

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

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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 \

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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