Eight"e*teth`e (?), a. [OE., fr. AS. eahtateóða; eahta eight + teóða tenth. Cf. Eighteenth, Tenth.] Eighteenth. [Obs.] Eight"fold` (?), a. Eight times a quantity. Eighth (tth), a. [AS. eahtoða.] 1. Next in order after the seventh.