silliness

from WordNet (r) 3.0 (2006)

silliness
    n 1: a ludicrous folly; "the crowd laughed at the absurdity of
         the clown's behavior" [syn: {absurdity}, {fatuity},
         {fatuousness}, {silliness}]
    2: an impulsive scatterbrained manner [syn: {giddiness},
       {silliness}]

from The Collaborative International Dictionary of English v.0.48

Silliness \Sil"li*ness\, n.
   The quality or state of being silly.
   [1913 Webster]