M / Mĕton
noun

Mĕton

gen. Mĕtōnis · gender masculine · decl. 3rd
or , , , = Μέτων
a celebrated Athenian astronomer, who discovered the cycle of nineteen years, at the end of which the new and full moons again fall on the same days
a celebrated Athenian astronomer, who discovered the cycle of nineteen years, at the end of which the new and full moons again fall on the same days, Avien. Prognost. 48; Aus. Epis. 2, 12.—Hence Cicero says, jestingly, of a debtor named Meton, who promised to pay in a year's time: quando iste Metonis annus veniet? Cic. Att. 12, 3, 2; cf. id. ib. 12, 51, 3.