molybdenum

American  

[muh-lib-duh-nuhm] / məˈlɪb də nəm /

noun

Chemistry.

1. a silver-white metallic element, used as an alloy with iron in making hard, high-speed cutting tools. Mo; 95.94; 42; 10.2.

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molybdenum British  

/ mɒˈlɪbdɪnəm /

noun

1. a very hard ductile silvery-white metallic element occurring principally in molybdenite: used mainly in alloys, esp to harden and strengthen steels. Symbol: Mo; atomic no: 42; atomic wt: 95.94; valency: 2–6; relative density: 10.22; melting pt: 2623°C; boiling pt: 4639°C

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molybdenum Scientific  

/ mə-lĭb′də-nəm /

1. A hard, silvery-white metallic element that resists corrosion and retains its strength at high temperatures. It is used to harden and toughen steel and to make high-temperature wiring. Molybdenum is an essential trace element in plant metabolism. Atomic number 42; atomic weight 95.96; melting point 2,623°C; boiling point 4,639°C; specific gravity 10.22 (at 20°C); valence 2, 3, 4, 5, 6.

2. See Periodic Table

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Etymology

Origin of molybdenum

First recorded in 1790–1800; from New Latin molybdēnum, alteration of earlier molybdēna “lead ore,” from Latin molybdaena, from Greek molýbdaina “galena,” equivalent to mólybd(os) “lead” + -aina a suffix indicating relationship or origin

Example Sentences

See Examples For:

molybdenum

On Feb. 4, 2025, Beijing issued Announcement No. 10, putting tungsten, tellurium, bismuth, molybdenum and indium-related items under export licensing.

From MarketWatch ● Aug. 7, 2026

Among the leading candidates is molybdenum disulfide, a material just three atoms thick, consisting of a layer of molybdenum between two layers of sulfur.

From Science Daily ● Jun. 17, 2026

"After that, we want to see whether the same approach works for related materials -- swapping molybdenum for tungsten, or sulfur for selenium -- to find out how broadly this idea can be applied."

From Science Daily ● Jun. 17, 2026

The company is targeting 3.1 billion pounds of copper, 650,000 ounces of gold, and 90 million pounds of molybdenum for 2026.

From Barron's ● Apr. 23, 2026

“He said that he wasn’t surprised, and when I asked him why, he said, ‘Well, now, you know molybdenum is a chemical element.

From "Silent To The Bone" by E.L. Konigsburg