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

See all Synonyms & Antonyms in Thesaurus 
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 Related Stories The footage, screened at international television confab MIPTV, showed extraordinary sights, including a bear making a treacherous half-mile descent down a crumbling cliff face, with two cubs clinging to her for life, images captured by a drone camera. —Liza Foreman, The Hollywood Reporter, 9 Apr. 2024 The film unveils the struggle of refugees navigating this treacherous terrain, where mines from the Balkan War lurk in the soil and political borders define lives. —Leo Barraclough, Variety, 8 Apr. 2024 See all Example Sentences for treacherous 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'treacherous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

Dictionary Entries Near treacherous

trc

treacherous

treachery

See More Nearby Entries 

Cite this Entry

“Treacherous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/treacherous. Accessed 18 Apr. 2024.

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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

Britannica English: Translation of treacherous for Arabic Speakers

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