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
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”
Explanation
Treacherous means either not trusted or dangerous. A treacherous road might be icy or otherwise likely to cause a car accident. A treacherous friend will betray you. Treachery refers to harmful acts you might do to someone who trusts you. It can also refer to being disloyal to your native country, but the word treason is more common in this sense. Treachery is from Middle English trecherie, from Old French, from trichier "to trick or cheat." The English word trick is from trikier, a slightly different spelling that was used in some dialects of Old French.
Vocabulary lists containing treacherous
List 2
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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.
Treacherous driving conditions on Saturday forced the closure of several highways near Lake Tahoe, including Interstate 80 over the Donner Summit.
From Seattle Times • May 5, 2024
Lindsey matted the hair of Zazie Beetz, who portrays the gun-toting Stagecoach Mary, while she created locks for Regina King’s tough-as-nails Treacherous Trudy Smith.
From New York Times • Apr. 28, 2022
"Treacherous" and "I Knew You Were Trouble" build into the earworm magnum opus "We are Never Ever Getting Back Together."
From Salon • Dec. 25, 2021
As the punks began to fade and hip-hop became the rhythm bed for state antagonism, they naturally fell in love with the Treacherous Three, Kurtis Blow and Grandmaster Flash.
From Los Angeles Times • Oct. 26, 2018
"Treacherous hounds!" said Bree, shaking his mane and stamping with his hoof.
From "The Horse and His Boy" by C.S. Lewis
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.
