treacherous

play
adjective treach·er·ous \ˈtre-chə-rəs, ˈtrech-rəs\

Definition of treacherous

  1. 1 :  characterized by or manifesting treachery :  perfidious

  2. 2a :  likely to betray trust :  unreliable <a treacherous memory>b :  providing insecure footing or support <treacherous quicksand>c :  marked by hidden dangers, hazards, or perils

treacherously

adverb

treacherousness

noun

Examples of treacherous in a sentence

  1. a treacherous act of betrayal

  2. They were not prepared to hike over such treacherous terrain.

  3. The snow made their hike all the more treacherous.

  4. Discussions about money can lead couples into treacherous territory.

14th Century

First Known Use of treacherous

14th century

Synonym Discussion of 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>.

TREACHEROUS Defined for English Language Learners

treacherous

play
adjective treach·er·ous \ˈtre-chə-rəs, ˈtrech-rəs\

Definition of treacherous for English Language Learners

  • : not able to be trusted : showing that someone cannot be trusted

  • : very dangerous and difficult to deal with


TREACHEROUS Defined for Kids

treacherous

play
adjective treach·er·ous \ˈtre-chə-rəs\

Definition of treacherous for Students

  1. 1 :  not safe because of hidden dangers <This was a treacherous road at night … — John Reynolds Gardiner, Stone Fox>

  2. 2 :  not trustworthy :  guilty of betrayal or likely to betray <a treacherous enemy>

treacherously

adverb


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