Foolish people are silly or senseless, and when you do something foolish, it's clearly unwise or irrational. Sitting on the hood of a car while your friend is driving is a foolish thing to do.

Things that show a lack of judgment are foolish, like cheating on a test or running into the street after a basketball. Foolish decisions at work can cost you your job, and foolish comments can hurt people's feelings. Foolish is a 14th century word that comes from fool, a person who's unwise. The Latin root, follis, means "bellows" or "leather bag." The "silly person" meaning comes from the figurative idea of a "windbag."

Definitions of foolish

adj devoid of good sense or judgment

foolish remarks”
“a foolish decision”
inadvisable, unadvisable
not prudent or wise; not recommended
ill-advised, unadvised
without careful prior deliberation or counsel
not politic
not prudent or wise
absurd, cockeyed, derisory, idiotic, laughable, ludicrous, nonsensical, preposterous, ridiculous
incongruous;inviting ridicule
asinine, fatuous, inane, mindless, vacuous
devoid of intelligence
cockamamie, cockamamy, goofy, sappy, silly, wacky, whacky, zany
ludicrous, foolish
absurd or silly because unlikely
harebrained, insane, mad
very foolish
ill-conceived, misguided
poorly conceived or thought out
rattlebrained, rattlepated, scatterbrained, scatty
lacking sense or discretion
showing or resulting from lack of judgment or wisdom
having or prompted by wisdom or discernment
worthy of being recommended or suggested; prudent or wise
advised, well-advised
having the benefit of careful prior consideration or counsel
marked by artful prudence, expedience, and shrewdness
careful and sensible; marked by sound judgment
all-knowing, omniscient
infinitely wise
perspicacious, sagacious, sapient
acutely insightful and wise
resembling an owl; solemn and wise in appearance
characterized by wisdom, especially the wisdom of God
having wisdom that comes with age and experience
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adj having or revealing stupidity

anserine, dopey, dopy, gooselike, goosey, goosy, jerky
lacking or marked by lack of intellectual acuity

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