Definition of Foolishness

Noun

fool·ish·ness (source)

1. The state or quality of being foolish; lack of good sense or judgement.

2. The act or instance of doing something irrational, senseless, or absurd.

Synonyms:

stupidity, absurdity, silliness, idiocy, nonsense, folly, imprudence, recklessness, tomfoolery

Antonyms:

wisdom, prudence, intelligence, sense, rationality