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1. An odd, fanciful or capricious idea
   "he had a whimsy about flying to the moon"; "whimsy can be humorous to someone with time to enjoy it";
   - notion, whim, whimsey
    
2. The trait of acting unpredictably and more from whim or caprice than from reason or judgment
   "I despair at the whimsy and whimsicality of my memory";
   - flightiness, arbitrariness, whimsicality, whimsey, capriciousness

Derived forms: whimsies

Type of: idea, irresponsibility, irresponsibleness, thought

Encyclopedia: Whimsy