treacherous
Americanadjective
-
characterized by faithlessness or readiness to betray trust; traitorous.
- Synonyms:
- treasonous, faithless, unfaithful
- Antonyms:
- loyal
-
deceptive, untrustworthy, or unreliable.
- Synonyms:
- deceitful
- Antonyms:
- reliable
-
unstable or insecure, as footing.
-
a treacherous climb.
adjective
-
betraying or likely to betray faith or confidence
-
unstable, unreliable, or dangerous
treacherous weather
treacherous ground
Other Word Forms
- treacherously adverb
- treacherousness noun
- untreacherous adjective
- untreacherousness noun
Etymology
Origin of treacherous
First recorded in 1300–50; Middle English trecherous, from Anglo-French, equivalent to trecher “deceiver” ( trech(ier) “to deceive” + -er -er 2 ) + -ous -ous; compare French tricheur “trickster”
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Answering that question is more treacherous than usual.
As the market has made clear in the first quarter, betting on Meta isn’t without risks: “Regulatory scrutiny persists, the trajectory of AI spending is unsustainable, and the macro remains treacherous,” White wrote.
From Barron's
But no-one had ever got close to it, for the Spirit always beat them back with howling blizzards and treacherous rockfalls.
From Literature
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"Whiteout conditions are expected and will make travel treacherous and potentially life-threatening," the NWS said.
From BBC
What the pair found was a desert highway that rolls up and down, like an asphalt serpent, with deadly blind peaks and treacherous hidden troughs.
From Barron's
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.