Lewis & Short

2. commentor, ōris, m. [comminiscor], one who devises or invents something, an inventor: uvae, i. e. Bacchus, Ov. F. 3, 785: fraudis, Auct. Ep. Iliad. 579: machinarius, a machinist, Scl. 5, § 13 Momms. (al. commentator).