The state or quality of being impish; mischievousness.(noun)
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Use "impishness" in a sentence
"Ishmael's reply was in that very formal tone that masked what in anyone else might have been termed impishness."
"With a schlubby, mustachioed Matt Damon and his part-trivial part-fantasy deadpan voiceover, Soderbergh is putting the impishness of his title character front and center."
"But he did it not from hauteur but from impishness."