(more mischievous; most mischievous)
1 : causing or tending to cause annoyance or minor harm or damage
a mischievous puppy/child
2 : showing a playful desire to cause trouble
mischievous behavior
a mischievous smile
3 : intended to harm someone or someone’s reputation
mischievous gossip
a mischievous lie
— mischievously adverb
She smiled mischievously.
— mischievousness noun (noncount)