<p><strong>Noun</strong></p><ul><li>lack of wisdom or good judgment; foolish quality: Oh, the foolishness of thinking that wealth brings happiness!</li><li>foolish talk, ideas, or behavior: How could someone with such a clever mind as yourself talk such foolishness?</li><li>a foolish act, error, habit, etc.: Shakespeare, who looks at all men as if from Mount Olympus, notes their foibles and foolishnesses, and yet smiles on them all.</li></ul>