indium

American  

[in-dee-uhm] / ˈɪn di əm /

noun

Chemistry.

1. a rare metallic element, soft, white, malleable, and easily fusible, found combined in various ore minerals, especially sphalerite: so called from the two indigo-blue lines in its spectrum. In; 114.82; 49; 7.3 at 20°C.

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indium British  

/ ˈɪndɪəm /

noun

1. a rare soft silvery metallic element associated with zinc ores: used in alloys, electronics, and electroplating. Symbol: In; atomic no: 49; atomic wt: 114.82; valency: 1, 2, or 3; relative density: 7.31; melting pt: 156.63°C; boiling pt: 2073°C

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indium Scientific  

/ ĭn′dē-əm /

1. A soft, malleable, silvery-white metallic element that occurs mainly in ores of zinc and lead. It is used in the manufacture of semiconductors, in bearings for aircraft engines, and as a plating over silver in mirrors. Atomic number 49; atomic weight 114.82; melting point 156.61°C; boiling point 2,080°C; specific gravity 7.31; valence 1, 2, 3.

2. See Periodic Table

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Etymology

Origin of indium

1860–65; < New Latin, equivalent to ind ( icum ) indigo + -ium -ium

Example Sentences

See Examples For:

indium

The Defense Logistics Agency has already asked for bids to stockpile up to 403 tons of indium over three years — more than a third of a year’s global output.

From MarketWatch ● Aug. 7, 2026

Most indium goes into coatings for flat-panel displays, a mature market.

From MarketWatch ● Aug. 7, 2026

The material contains micrometer-scale gold crenelated structures positioned above an insulating layer and a semiconductor made from a mixture of indium and antimony.

From Science Daily ● Jul. 31, 2026

The cylinder itself is sealed with a thin protective layer of a soft, malleable metal called indium.

From Barron's ● Jul. 2, 2026

The most abundant source at present known is the Freiberg blende, 100,000 parts of which only yield from twenty-five to forty parts of indium.

From Field's Chromatography or Treatise on Colours and Pigments as Used by Artists by Thomas Salter