*  Manganese | Define Manganese at Dictionary.com
... manganese dioxide) is a valuable oxidizing agent: used chiefly as an alloying agent in steel to give it toughness. Symbol: Mn; ... Manganese definition, a hard, brittle, grayish-white, metallic element, an oxide of which, MnO 2 ( ... manganese in Medicine Expand. manganese man·ga·nese (māng'gə-nēz', -nēs'). n. Symbol Mn. A brittle metallic element, having ... Word Origin and History for manganese Expand. n. 1670s as the name of a mineral, oxide of manganese, from French manganèse (16c ...
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