seofonteoþa [OE] sevententhe [MI] seventeenth [ME] seventínþ https://www.etymonline.com/word/seventeenth#etymonline_v_48733 https://www.merriam-webster.com/dictionary/seventeenth https://quod.lib.umich.edu/m/middle-english-dictionary/dictionary/MED39690 https://bosworthtoller.com/27462