Meaning of the word insidious in English

What does insidious mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

insidious

US /ɪnˈsɪd.i.əs/
UK /ɪnˈsɪd.i.əs/

Adjective

1.

proceeding in a gradual, subtle way, but with harmful effects

Example:
The disease is insidious and often goes undetected until it's too late.
The insidious rumors slowly destroyed his reputation.
2.

treacherous; crafty

Example:
He made an insidious attempt to undermine her authority.
The politician's insidious tactics were designed to mislead the public.
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