19th century. Borrowed from German orfe, orf, possibly from French orphe or Old High German orvo, from Latin orphus (“gilt-head bream”), from Ancient Greek ὀρφώς (orphṓs, “sea perch”).
May be related to Old English eorp, earp (“dark, dusky”), Old High German erpf (“brown”), Old Norse jarpr (“brown”), and Ancient Greek ὀρφνός (orphnós, “dark”).