impish
AdjectiveWordNet 3.0
Webster's Dictionary (GCIDE)
impish \imp"ish\ ([i^]mp"[i^]sh), a. Having the qualities, or showing the characteristics, of an imp; naughtily or annoyingly playful; as, teasing and worrying with impish laughter.
Syn: elfish, elvish, implike, mischievous, pixilated, prankish, puckish. [1913 Webster + WordNet 1.5]