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 same approach allowed it to dominate rare earths, gallium, germanium and graphite—keeping prices low enough to push Western producers out of the market.

From The Wall Street Journal ● Aug. 24, 2026

Leading the charge is the Defense Department, which unleashed a spree of deals securing equity in future gallium producer Atlantic Alumina and Canadian mining company Trilogy Metals.

From MarketWatch ● Aug. 5, 2026

Alcoa and the governments of Australia, Japan and the U.S. will build a gallium production plant at Alcoa’s Wagerup refinery in Western Australia.

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

The precipitate is dissolved in hydrochloric acid and foreign metals are removed by sulphuretted hydrogen; the residual liquid being then fractionally precipitated by sodium carbonate, which throws out the gallium before the zinc.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 4 "G" to "Gaskell, Elizabeth" by Various