eahtoða [OE]
eighthe [MI]
eighth [ME]
éþ
https://www.etymonline.com/word/eighth#etymonline_v_32177
https://www.merriam-webster.com/dictionary/eighth
https://quod.lib.umich.edu/m/middle-english-dictionary/dictionary/MED13156
https://bosworthtoller.com/8377