Meaning of the word foolishness in English

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

foolishness

US /ˈfuː.lɪʃ.nəs/
UK /ˈfuː.lɪʃ.nəs/

Noun

lack of good sense or judgment; stupidity

Example:
His foolishness led to a series of embarrassing mistakes.
It was pure foolishness to try and climb that mountain without proper gear.