alumina

American  

[uh-loo-muh-nuh] / əˈlu mə nə /

noun

1. the natural or synthetic oxide of aluminum, Al 2 O 3 , occurring in nature in a pure crystal form as corundum.

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alumina British  

/ əˈluːmɪnə /

noun

1. another name for aluminium oxide

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alumina Scientific  

/ ə-lo̅o̅′mə-nə /

1. Any of several forms of aluminum oxide used in aluminum production and in abrasives, refractories, ceramics, and electrical insulation. Alumina occurs naturally as the mineral corundum and, with minor traces of chromium and cobalt, as the minerals ruby and sapphire, respectively. In its hydrated form it also occurs as the rock bauxite. Also called aluminum oxide. Chemical formula: Al ₂ O ₃ .

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Etymology

Origin of alumina

1780–90; < Latin alūmin-, stem of alūmen alum ¹ + -a ⁴

Compare meaning

How does alumina compare to similar and commonly confused words? Explore the most common comparisons:

• alumina vs. aluminum

Example Sentences

See Examples For:

alumina

Loh says lower alumina prices could also allow Press Metal to reduce hedging.

From The Wall Street Journal ● Aug. 28, 2026

Aluminum prices are expected to remain supported by a supply deficit in 2026, while still subdued alumina prices should continue to support smelting margins, he reckons.

From The Wall Street Journal ● Aug. 10, 2026

Official Irish data published earlier this month showed half the refinery's alumina exports in the first quarter went to Russia, up from 43 percent last year, while 40 percent went to the EU.

From Barron's ● Jul. 24, 2026

The investigation was however unable to determine where alumina was traded once it entered Russia because of a lack of internal Russian trade data, he added.

From Barron's ● Jul. 24, 2026

Pertaining to or containing alum, or alumina; as, aluminous minerals, aluminous solution.

From Webster's Unabridged Dictionary by Noah Webster