niobium

American  

[nahy-oh-bee-uhm] / naɪˈoʊ bi əm /

noun

Chemistry.

1. a steel-gray metallic element resembling tantalum in its chemical properties; becomes a superconductor below 9 K; used chiefly in alloy steels. Nb; 41; 92.906; 8.4 at 20°C.

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niobium British  

/ naɪˈəʊbɪəm /

noun

1. Former name: columbium.  a ductile white superconductive metallic element that occurs principally in columbite and tantalite: used in steel alloys. Symbol: Nb; atomic no: 41; atomic wt: 92.90638; valency: 2, 3, or 5; relative density: 8.57; melting pt: 2469±10°C; boiling pt: 4744°C

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niobium Scientific  

/ nī-ō′bē-əm /

1. A soft, silvery, ductile metallic element that usually occurs in nature together with the element tantalum. It is used to build nuclear reactors, to make steel alloys, and to allow magnets to conduct electricity with almost no resistance. Atomic number 41; atomic weight 92.906; melting point 2,468°C; boiling point 4,927°C; specific gravity 8.57; valence 2, 3, 5.

2. See Periodic Table

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Etymology

Origin of niobium

From New Latin, dating back to 1835–45; see origin at Niobe, -ium

Example Sentences

Niobium is a critical metal used to strengthen steel and support clean energy technologies, and its origins are tied to dramatic geological events that unfolded more than 800 million years ago.

From Science Daily • Jan. 23, 2026

Niobium is not the only material that startups are exploring.

From Reuters • Jul. 11, 2022

Niobium is a stable metal often used to strengthen steel - the world's largest deposits are in Brazil and Canada.

From Reuters • Jul. 11, 2022

Niobium is mixed with steel to make the alloy stronger, lighter and more heat and corrosion resistant.

From Seattle Times • Dec. 22, 2021

Niobium, nī-ō′bi-um, n. a rare metal, steel-gray in colour, discovered in the mineral Tantalite—sometimes called Columbium.

From Chambers's Twentieth Century Dictionary (part 3 of 4: N-R) by Various