The Collaborative International Dictionary of English v.0.48:
fatuousness \fatuousness\ n. a ludicrous folly. Syn: absurdity, fatuity, silliness. [WordNet 1.5] fatwaWordNet (r) 3.0 (2006):
fatuousness n 1: a ludicrous folly; "the crowd laughed at the absurdity of the clown's behavior" [syn: absurdity, fatuity, fatuousness, silliness]