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.

---

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

---

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

---

Etymology

Origin of indium

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

Example Sentences

That puts a dent in its 5,867% gain in the past 12 months, as investors bet on explosive demand for its indium phosphide substrates, used for optical—networking and photonic components within data centers.

From Barron's • Apr. 21, 2026

"This 'shadow' of indium doesn't completely disappear. The memory is not erased."

From Science Daily • Mar. 13, 2026

The process results in new alloys that can imitate platinum, silver and indium.

From The Wall Street Journal • Dec. 10, 2025

For example, car batteries are often reliant on lithium, while indium is a rare metal used for touch screens.

From BBC • Jun. 3, 2025

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 Salter, Thomas