mischievous in WordNet English dictionary

1. naughtily or annoyingly playful
   "teasing and worrying with impish laughter"; "a wicked prank"
   arch  impish  implike  mischievous  pixilated  prankish  puckish  wicked 
   
2. deliberately causing harm or damage
   "mischievous rumors and falsehoods"
   mischievous