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

See Examples For:

gallium

The company earlier this week said it had reached an agreement with the governments of Australia, Japan and the U.S. to build a gallium production plant in Western Australia.

From The Wall Street Journal ● Jul. 16, 2026

The facility is intended to create a new source of gallium, a critical mineral used in semiconductors and defense applications.

From The Wall Street Journal ● Jul. 14, 2026

In an earlier project, Gaston, Lambie, and Steenbergen used liquid gallium to crystallize zinc into intricate `snowflake' structures.

From Science Daily ● Jul. 9, 2026

A better understanding of how gallium changes with temperature could benefit nanotechnology, where researchers manipulate matter at extremely small scales to create new materials with specialized properties.

From Science Daily ● Jul. 9, 2026

The mine might or might not be of consequence; gallium was used in a number of industrial processes, but beyond that was not particularly valuable.

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