manganese

A metallic element resembling and often associated, particularly in ores, with iron; atomic no. 25, atomic wt. 54.94; manganous salts are sometimes used in medicine. SYN: manganum. [Mod. L. manganesium, manganum, an altered form of magnesium]

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man·ga·nese 'maŋ-gə-.nēz, -.nēs n a grayish white usu. hard and brittle metallic element that resembles iron but is not magnetic symbol Mn see ELEMENT (table)

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n.

a greyish metallic element, the oxide of which, when inhaled by miners in underventilated mines, causes brain damage and symptoms very similar to those of parkinsonism. Minute quantities of the element are required by the body (see trace element). Symbol: Mn.

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man·ga·nese (Mn) (mangґgə-nēs) [L. manganum, manganesium] a metal resembling iron; atomic number 25, atomic weight 54.938, specific gravity 7.2. It occurs normally throughout the body, concentrated in the mitochondria, chiefly in the pituitary, liver, pancreas, kidney, and bone; it is necessary for the synthesis of mucopolysaccharides and activates a number of enzymes. Clinical deficiency is unknown in humans but may occur in other animals and causes perosis in poultry. Excessive inhalation of manganese dust can cause toxicity; see under poisoning and pneumonitis.