Main entry: whimsey, whimsicality, whimsy, arbitrariness, capriciousness, flightiness
Definition: the trait of acting unpredictably and more from whim or caprice than from reason or judgment
Usage: I despair at the flightiness and whimsicality of my memory
Main entry: capriciousness, unpredictability
Definition: the quality of being guided by sudden unpredictable impulses