Noun whimsy has 2 senses
- notion, whim, whimsy, whimsey - an odd or fanciful or capricious idea; "the theatrical notion of disguise is associated with disaster in his stories"; "he had a whimsy about flying to the moon"; "whimsy can be humorous to someone with time to enjoy it"
--1 is a kind of idea, thought
- flightiness, arbitrariness, whimsicality, whimsy, whimsey, capriciousness - 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"
--2 is a kind of irresponsibility, irresponsibleness
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