foolish
/ˈfuːlɪʃ/
adjective
[more foolish; most foolish]
A foolish man reading a newspaper on railroad tracks
Definition of FOOLISH
: having or showing a lack of good sense or judgment : STUPID, SILLY
a foolish decision/mistake
He was wearing a foolish grin.
She's been taking foolish risks.
— foolishness noun [noncount]