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

See Examples For:

tantalum

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

In addition to lithium, Somaliland is rich in tantalum and niobium -- critical minerals for electronics -- as well as gold, copper, and emeralds, according to the ministry, though quantities have yet to be verified.

From Barron's ● Feb. 25, 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

Bahrami noted that tantalum stands out because it is extremely durable and can withstand the harsh cleaning used to remove contamination during fabrication.

From Science Daily ● Nov. 17, 2025

Some metals, as for instance, osmium, tantalum, thorium, and others, have been used, and others, also, with great success, so that the march of improvements is now going forward with rapid strides.

From Electricity for Boys by James Slough Zerbe