D defs.my
Entry 2 senses Webster, 1913

Foolishness

· Fool·ish·ness · IPA /ˈfuːlɪʃnəs/
01 n. The quality of being foolish.
  1. 1.
    The quality of being foolish.
  2. 2.
    A foolish practice; an absurdity.
    “The preaching of the cross is to them that perish foolishness.” — 1 Cor. i. 18.