Showing results for alumina. Search instead for aluminas.

alumina

American

[uh-loo-muh-nuh] / əˈlu mə nə /

noun

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

alumina British

/ əˈluːmɪnə /

noun

another name for aluminium oxide

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

alumina Scientific

/ ə-lo̅o̅′mə-nə /

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 .

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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

alumina

Norsk Hydro NHY -0.91%decrease; red down pointing triangle said it expects a further financial hit in the fourth quarter following gas supply challenges at its alumina refinery in Brazil.

From The Wall Street Journal ● Oct. 6, 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

Press Metal is still projected to post record annual earnings over the coming years as its alumina plant, due to begin operations in early 2027, improves its cost structure, he adds.

From The Wall Street Journal ● Jul. 28, 2026

Production in Ireland was launched in 1983, and the company says it produces around 1.9 million tonnes of alumina a year at the plant.

From Barron's ● Jul. 24, 2026

A mineral of the feldspar family, triclinic in crystallization, and in composition a silicate of alumina and soda.

From Webster's Unabridged Dictionary by Noah Webster

Random Word

Spin the wheel and learn a new word!

Get a word

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023