Pronunciation: (mang'gu-nīt"), [key]
1. a gray to black mineral, hydrous manganese oxide, MnO(OH); gray manganese ore.
2. Chem.any of a series of salts containing tetravalent manganese and derived from either of two acids, H4MnO4 or H2MnO3.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.