[ uh-loo-muh-nuh ]
/ əˈlu mə nə /


the natural or synthetic oxide of aluminum, Al2O3, occurring in nature in a pure crystal form as corundum.

Origin of alumina

1780–90; < Latin alūmin-, stem of alūmen alum1 + -a4
Also called aluminum oxide. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for alumina

British Dictionary definitions for alumina

/ (əˈluːmɪnə) /


another name for aluminium oxide

Word Origin for alumina

C18: from New Latin, plural of Latin alūmen alum
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

Science definitions for alumina

[ ə-lōōmə-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: Al2O3.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.