Meaning & use

treacherous

adjective·Academic

Guilty of betrayal or likely to betray trust; also, dangerous due to hidden or unpredictable hazards.

See it in a sentence

The icy mountain road was treacherous, forcing drivers to slow to a crawl.

His treacherous business partner secretly sold company secrets to a rival firm.

A note on using this word

Treacherous applies both to people who betray trust and to physical conditions, like weather or terrain, that hide serious danger.

Words with a similar meaning

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Words with an opposite meaning

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