reducˈtorial,a.rare. [f. as reduct v. + -orial.] = reductive a. 1788T. Taylor Proclus (1792) II. 409 Every reductorial cause..in the gods differs both from a cathartic or purifying cause, and from convertive genera.1816― in Pamphleteer VIII. 478 Intellect is of a reductorial or convertive nature.