treacherous

adjective

treach·​er·​ous ˈtre-chə-rəs How to pronounce treacherous (audio)
ˈtrech-rəs
Synonyms of treacherousnext
1
a
: 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
treacherously adverb
treacherousness noun

Synonyms

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Whiteout conditions are possible and could make travel conditions treacherous and potentially life-threatening. — Forum News Service, Twin Cities, 4 Mar. 2025 The climate, meanwhile, continues on a treacherous path of warming. — Brent Crane, The New Yorker, 2 Mar. 2025 In the days after the Palisades fire, those Q and A segments were occasionally treacherous for Bass. — David Zahniser, Los Angeles Times, 22 Feb. 2025 But their strategy is also a tacit acknowledgment of the treacherous path their party’s tax and spending package faces in the House. — Catie Edmondson, New York Times, 21 Feb. 2025 See All Example Sentences for treacherous

Word History

First Known Use

14th century, in the meaning defined at sense 2

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

Rhymes for treacherous

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Browse Nearby Words

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treacherous
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Cite this Entry

“Treacherous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/treacherous. Accessed 10 Mar. 2025.

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Kids Definition

treacherous

adjective
treach·​er·​ous ˈtrech-(ə-)rəs How to pronounce treacherous (audio)
1
a
: guilty of treachery
b
: likely to betray : unreliable
a treacherous memory
2
: giving a false appearance of safety or solidity
a treacherous stretch of bog
treacherously adverb

More from Merriam-Webster on treacherous

Nglish: Translation of treacherous for Spanish Speakers

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