Word a Day
insidious
What does insidious mean?
insidious (adjective): causing harm in a stealthy, often gradual, manner.
Definition: Wiktionary, CC BY-SA 4.0.
How do you pronounce insidious?
/ɪnˈsɪdiəs/ (IPA, American English). The app reads every word aloud.
Where does insidious come from?
From Middle French insidieux, from Latin īnsidiōsus (“cunning, artful, deceitful”).
Etymology: Wiktionary, CC BY-SA 4.0.
Test yourself: do you know “insidious”?
Tap an answer to check it. The same questions the app asks.
What does “insidious” mean?
having brief brilliant points or flashes of light
Not quite: that's what glittery means.
ordinary; not new; part of the mainstream culture
Not quite: that's what mundane means.
being or operating under the surface of the earth
Not quite: that's what subterranean means.
causing harm in a stealthy, often gradual, manner
Right! That's what “insidious” means.
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