tantalum

American  

[tan-tl-uhm] / ˈtæn tl əm /

noun

Chemistry.

1. a gray, hard, rare, metallic element occurring in columbite and tantalite and usually associated with niobium: used, because of its resistance to corrosion by most acids, for chemical, dental, and surgical instruments and apparatus. Ta; 180.948; 73; 16.6.

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tantalum British  

/ ˈtæntələm /

noun

1. a hard greyish-white metallic element that occurs with niobium in tantalite and columbite: used in electrical capacitors in most circuit boards and in alloys to increase hardness and chemical resistance, esp in surgical instruments. Symbol: Ta; atomic no: 73; atomic wt: 180.9479; valency: 2, 3, 4, or 5; relative density: 16.654; melting pt: 3020°C; boiling pt: 5458±100°C

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tantalum Scientific  

/ tăn′tə-ləm /

1. A hard, heavy, gray metallic element that is highly resistant to corrosion at low temperatures. It is used to make light-bulb filaments, surgical instruments, and glass for camera lenses. Atomic number 73; atomic weight 180.948; melting point 3,017°C; boiling point 5,458°C; specific gravity 16.6; valence 2, 3, 4, 5.

2. See Periodic Table

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Etymology

Origin of tantalum

1795–1805; < New Latin; named after Tantalus

Example Sentences

With no local testing or controls of exports, secondary minerals like tantalum, beryl and tin were being shipped out undetected and untaxed.

From Barron's • Mar. 26, 2026

The company also said it continues to strengthen industrywide supply-chain due diligence, and last year told suppliers to stop obtaining tin, tungsten, tantalum and gold from Congo and neighboring Rwanda.

From The Wall Street Journal • Dec. 8, 2025

Growing tantalum directly on silicon required solving several technical problems related to how the two materials interact, but the researchers succeeded and uncovered significant advantages in the process.

From Science Daily • Nov. 17, 2025

Last year Rwandan mining company Trinity Metals secured a $3.9m grant from the DFC to help develop the three mines that it owns in the country, producing tin, tantalum and tungsten.

From BBC • Nov. 9, 2025

There is no tantalum on Mars except a little scattered through tons of rock.

From Giants on the Earth by Meek, S. P. (Sterner St. Paul)