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Friday, May 30, 2025
Word of the Day

insidious

adjective

Proceeding in a gradual, subtle way, but with harmful effects; treacherous; crafty.

Intermediate - Known to most educated speakers

Etymology

From Latin insidiosus "deceitful, cunning," from insidiae "ambush, plot," from insidere "to sit in, lie in wait," from in- + sedere "to sit."

Examples in Use

  • 1.

    "The insidious disease progressed without obvious symptoms."

  • 2.

    "Propaganda has an insidious effect on public opinion."

  • 3.

    "The insidious rumor slowly destroyed her reputation."

Related Vocabulary

Synonyms

subtlestealthycunningtreacherouscrafty

Related Words

sneakyslydeceptivepernicious

Fun Fact

Insidious literally means "sitting in ambush"—hidden danger that attacks gradually. The word captures threats that are more dangerous because they're not immediately obvious.

Word Game Tips

Letters: 9 letters (I, N, S, I, D, I, O, U, S)

Scrabble Value: 10 points

Tip: Words ending in "US" are often good scoring opportunities.

Put Your Vocabulary to the Test!

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