elf

noun pl. elves

1. Folklore a tiny, often prankish being in human form, exercising magic powers and haunting woods and hills; sprite
2. a small child or being, esp. a mischievous one

Origin: ME < OE ælf, akin to OHG alb (Ger, nightmare), prob. < IE base *albho-, white > L albus, white: prob. basic sense “whitish figure” (in the mist)