From Middle English eighte, aught, eahte, ahte, from Old English eahta, from Proto-West Germanic *ahtō, from Proto-Germanic *ahtōu, from Proto-Indo-European *oḱtṓw.
Cognate with Scots aucht ("eight"), West Frisian acht ("eight"), Dutch acht ("eight"), Low German acht ("eight"), German acht ("eight"), Norwegian åtte ("eight"), Swedish åtta ("eight"), Icelandic átta ("eight"), Latin octo ("eight"), Ancient Greek ὀκτώ, Irish ocht ("eight").