Late Middle English, from Late Latin orphanus, from Ancient Greek ὀρφανός (orphanós, “without parents, fatherless”), from Proto-Indo-European *h₃órbʰos. PIE word *h₃órbʰos Cognate with Sanskrit अर्भ (árbha), Latin orbus (“orphaned”), Old High German erbi, arbi (German Erbe (“heir”)), Old English ierfa (“heir”). More at erf.