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Synonyms for Whimsicality (same or very similar meaning)

WordNet sense 1 (the trait of acting unpredictably and more from whim or caprice than from reason or judgment):
arbitrariness, capriciousness, flightiness, whimsey, whimsy

WordNet sense 2 (the trait of behaving like an imp):
impishness, mischievousness, puckishness

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