I.a former, fashioner (post-Aug.).
II. Trop.: “praeceptor rector est alienorum ingeniorum ac formator,” Quint. 10, 2, 20; so, “animi (with praeceptor virtutis),” Col. 1 praef. § “4: morum (with magister),” Plin. Ep. 8, 23, 2: “agricolae,” Pall. 1, 1.