[syn: impishness, mischievousness, puckishness, whimsicality]
The Collaborative International Dictionary of English v.0.48:
Whimsicality \Whim`si*cal"i*ty\, n.
   The quality or state of being whimsical; whimsicalness.
   [1913 Webster]
WordNet (r) 3.0 (2006):
whimsicality
    n 1: the trait of acting unpredictably and more from whim or
         caprice than from reason or judgment; "I despair at the
         flightiness and whimsicality of my memory" [syn:
         flightiness, arbitrariness, whimsicality, whimsy,
         whimsey, capriciousness]
    2: the trait of behaving like an imp [syn: impishness,
       mischievousness, puckishness, whimsicality]