treacherous
TRECH-er-uss
/ˈtretʃ.ər.əs/
Guilty of or involving betrayal; also presenting hidden, unpredictable physical dangers.
Dual usage: can describe a betraying person or physically dangerous environmental conditions.
The story behind the word. The word traveled into English from Old French tricherie (trickery). It is closely linked to 'traitor' (from Latin tradere, to hand over across enemy lines). Thus, a treacherous person is someone ready to hand you over.
Word relationships
- perfidious: Perfidious emphasizes breach of sacred vows, whereas treacherous applies to both human betrayal and physical hazards.
- hazardous: Hazardous implies physical danger, but treacherous implies hidden, deceptive danger.
- loyal: Loyal means showing firm, constant support.
- safe: Safe means free from danger or risk.
Commonly confused with
- treasonous: Treasonous specifically means committing high treason against state or sovereign, whereas treacherous is broader.
Word family
- treachery (noun): Violation of faith or betrayal of trust.
- treacherously (adverb): In a treacherous or betraying manner.
Collocations
- treacherous water
- treacherous ally
- treacherous road
Idioms & expressions
- snake in the grass
- skating on thin ice
Example sentences
- "The mountain pass was treacherous during winter storms, with hidden ice slicking the steep narrow trails." Physical danger
Memory hook
TREACHEROUS roads have TRICKS that cause TRAGEDY. Betraying trust or hidden danger.
When not to use
Do not use for open conflict; treachery requires hidden danger or betrayal of safety.
Fun facts
- In Dante's Inferno, the deepest 9th circle of Hell is reserved not for violent criminals, but for treacherous traitors.
Related words
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