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