gallium

American  

[gal-ee-uhm] / ˈgæl i əm /

noun

Chemistry.

1. a rare, steel-gray, trivalent metallic element used in high-temperature thermometers because of its high boiling point (1983°C) and low melting point (30°C). Ga; 69.72; 31; 5.91 at 20°C.

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gallium British  

/ ˈɡælɪəm /

noun

1. a silvery metallic element that is liquid for a wide temperature range. It occurs in trace amounts in some ores and is used in high-temperature thermometers and low-melting alloys. Gallium arsenide is a semiconductor. Symbol: Ga; atomic no: 31; atomic wt: 69.723; valency: 2 or 3; relative density: 5.904; melting pt: 29.77°C; boiling pt: 2205°C

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gallium Scientific  

/ găl′ē-əm /

1. A rare, silvery metallic element that is found as a trace element in coal, in bauxite, and in several minerals. It is liquid near room temperature and expands when it solidifies. It is used in thermometers and semiconductors. Atomic number 31; atomic weight 69.72; melting point 29.78°C; boiling point 2,403°C; specific gravity 5.907; valence 2, 3.

2. See Periodic Table

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Etymology

Origin of gallium

1870–75; < New Latin, equivalent to Latin gall ( us ) cock (translation of French coq, from Lecoq de Boisbaudran, 19th-century French chemist) + New Latin -ium -ium

Example Sentences

Constitution and that if you try to stir some soup with a spoon made of the element gallium, the spoon will disappear into the bowl—all thanks to my troubles with sleep.

From The Wall Street Journal • Apr. 17, 2026

"There is a dramatic change in the lattice when you shine light on it, a unique phenomenon that you don't see with silicon or gallium arsenide," Leite said.

From Science Daily • Mar. 31, 2026

Perovskites are a type of semiconductor, but they behave very differently from traditional materials like silicon and gallium arsenide.

From Science Daily • Mar. 31, 2026

There are no substitutes for gallium, a soft metal that is used to make the semiconductors needed for high-speed electronics, LEDs, lasers, and medical imaging.

From Barron's • Mar. 9, 2026

He'd thought the mention of gallium would do it.

From Forget Me Nearly by Wallace, F. L. (Floyd L.)