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.

---

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

---

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

---

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

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

The name gallium comes from Gaul, the ancient Latin name for France, honoring the nationality of its discoverer.

From Science Daily ● Jul. 9, 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

Dorn Starret, owner of a gallium mine on Ceres.

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