octōgōnŏs: (octāgōnŏs), i, adj., = ὀκτώ-γωνία>,I eight-cornered, octagonal: turris marmorea octogonos, Vitr. 1, 6, 4.— As subst.: octōgōnum, i, n., an octagon, Vitr. 1, 6, 4 al.