- a member of the pyroxene group of minerals having an orthorhombic crystal structure, such as enstatite and hypersthene
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 variety of the mineral pyroxene that crystallizes in the orthorhombic system and contains no calcium and little or no aluminum. Enstatite is an orthopyroxene.
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