A sudden, unpredictable change of mood or behavior; a whim or sudden decision made without good reason.
From Italian 'capriccio' (whim), possibly from 'capra' (goat) plus 'riccio' (hedgehog), or possibly from capo (head) with the idea of sudden head movements. Entered English in the 1600s.
The possible connection to a hedgehog's jerky movements is poetic but probably wrong—however, the idea that whimsy comes from animal behavior stuck in multiple languages, showing how metaphors about animals describe human unpredictability across cultures.
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