M / mercātĭo
noun

mercātĭo

gen. mercātōnis · gender feminine · decl. 3rd
a dealing in wares, mercantile dealing
a dealing in wares, mercantile dealing (post-class.): pecunia in mercationibus perdita, in mercantile speculations, Gell. 3, 3, 14; Firm. Math. 3, 8 fin.