alumina

[uh-loo-muh-nuh]
noun
the natural or synthetic oxide of aluminum, Al 2 O 3 , occurring in nature in a pure crystal form as corundum.
Also called aluminum oxide.


Origin:
1780–90; < Latin alūmin-, stem of alūmen alum1 + -a4

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World English Dictionary
alumina (əˈluːmɪnə)
 
n
another name for aluminium oxide
 
[C18: from New Latin, plural of Latin alūmenalum]

Collins English Dictionary - Complete & Unabridged 10th Edition
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American Heritage
Science Dictionary
alumina   (ə-l'mə-nə)  Pronunciation Key 
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: Al2O3.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Britannica
Encyclopedia

alumina

synthetically produced aluminum oxide (Al2O3), a white or nearly colourless crystalline substance that is used as a starting material for the smelting of aluminum metal. It also serves as the raw material for a broad range of advanced ceramic products and as an active agent in chemical processing.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences for alumina
The pozzolanic mortar used had a high content of alumina and silica.
Alumina, grain, gypsum, logs and wood chips, for instance, are bulk cargoes.
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