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

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 Many of its young and able-bodied citizens have fled the country, choosing treacherous routes along the Sahara over military service at home. Selam Gebrekidan, New York Times, "Ethiopia and Eritrea, Longtime Foes, Meet for Peace Talks," 8 July 2018 The journey to the U.S. is treacherous and life-threatening — turning away migrants on the border is often akin to signing someone’s death warrant. Mekita Rivas, Teen Vogue, "It's Not OK to Appropriate Mexican Culture — Especially If You’re Dehumanizing Its People," 28 June 2018 There’s a huge bailout area to the right of the green, but the putting surface slopes severely down toward the water so chipping can be extremely treacherous. Brent Kennedy, Howard County Times, "Renditions Golf Course," 1 June 2018 The NexTurf that was installed at Veterans Stadium was so treacherous that Ravens coach Brian Billick refused to play a preseason game in 2001. Ed Barkowitz,, "Bryan Colangelo mess inspires memories of Wilt, T.O. and a Spectrum melee," 31 May 2018 Even further north and west in Huron, Tuscola and Sanilac counties the outlook is even more treacherous. Detroit Free Press, "More snow coming for Wayne, Oakland and Livingston counties," 7 Mar. 2018 Ormand, now chairman and CEO, is widely credited with getting Lilis to this point, avoiding bankruptcy while navigating a treacherous road of headquarter relocations and several CEO changes. Jordan Blum, San Antonio Express-News, "Lilis may be an acquisition target," 13 July 2018 Even so, the Strait is a busy shipping lane with treacherous currents. Fox News, "The Latest: Spain: Over 1,000 rescued at sea in last 3 days," 25 June 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

19 Sep 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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