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

Alcoa said it and the governments of Australia, Japan and the U.S. have reached a final investment decision to build a gallium production plant at the company’s Wagerup alumina refinery in Western Australia.

From The Wall Street Journal ● Jul. 15, 2026

Nearly 150 years after gallium was first discovered and added to the periodic table, scientists at the University of Auckland have uncovered previously unknown details about the metal's atomic structure and behavior.

From Science Daily ● Jul. 9, 2026

On industrial policy, a group of 10 EU members is working on a pilot project to stockpile critical raw materials such as rare-earth elements and gallium, a crucial component in semiconductors.

From The Wall Street Journal ● Jul. 6, 2026

It’s harder than ever to buy the rare metal gallium from China for your high-tech military radar system—but it’s easier than ever to buy Chinese soft-serve ice cream in the U.S.

From Barron's ● Jun. 1, 2026

The metal gallium shows this excellently well, keeping liquid for years until touched with the solid metal, when there is a considerable rise of temperature as solidification takes place.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 1 "Evangelical Church Conference" to "Fairbairn, Sir William" by Various