manganesian,a.|mæŋgəˈniːz(ɪ)ən| [f. manganese + -ian.] Pertaining to manganese, or characterized by its presence. 1795W. Nicholson Dict.Chem. II. 596 This powdery manganesian ore.1837J. T. Smith tr.Vicat's Mortars 2 The argillaceous, magnesian,..manganesian [etc., varieties of limestone].