manganese

American  

[mang-guh-nees, -neez] / ˈmæŋ gəˌnis, -ˌniz /

noun

Chemistry.

1. a hard, brittle, grayish-white, metallic element, an oxide of which, MnO 2 manganese dioxide, is a valuable oxidizing agent: used chiefly as an alloying agent in steel to give it toughness. Mn; 54.938; 25; 7.2 at 20°C.

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manganese British  

/ ˈmæŋɡəˌniːz /

noun

1. a brittle greyish-white metallic element that exists in four allotropic forms, occurring principally in pyrolusite and rhodonite: used in making steel and ferromagnetic alloys. Symbol: Mn; atomic no: 25; atomic wt: 54.93805; valency: 1, 2, 3, 4, 6, or 7; relative density: 7.21–7.44; melting pt: 1246±3°C; boiling pt: 2062°C

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manganese Scientific  

/ măng′gə-nēz′ /

1. A grayish-white, hard, brittle metallic element that occurs in several different minerals and in nodules on the ocean floor. It is used to increase the hardness and strength of steel and other important alloys. Atomic number 25; atomic weight 54.9380; melting point 1,244°C; boiling point 1,962°C; specific gravity 7.21 to 7.44; valence 1, 2, 3, 4, 6, 7.

2. See Periodic Table

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Etymology

Origin of manganese

1670–80; < French manganèse < Italian manganese, alteration of Medieval Latin magnesia magnesia

Example Sentences

He highlights the strong performance of Sierra Gorda, Cannington and Australian Manganese.

From The Wall Street Journal • Feb. 12, 2026

Manganese is widely available and low cost, making it an attractive alternative to expensive metals.

From Science Daily • Feb. 3, 2026

Manganese antioxidants form as a result of radiation exposure, and the more that form, the more radiation the microbes can resist.

From Scientific American • Oct. 27, 2022

Two mines are on the route, including the Ghana Manganese Mine at Nsuta and a bauxite mine at Awaso, which used to use the railway until it collapsed, according to the ministry.

From Reuters • Jul. 19, 2022

Manganese is mined in Minas Geraes for export.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 4 "Bradford, William" to "Brequigny, Louis" by Various