corundum
[ kuh-ruhn-duh m ]
/ kəˈrʌn dəm /
noun
a common mineral, aluminum oxide, Al2O3, notable for its hardness: transparent varieties, as sapphire and ruby, are used as gems, other varieties as abrasives: often made synthetically.
RELATED WORDS
jewel, gem, rhinestone, paragon, ice, lozenge, rock, zircon, rhombus, allotrope, solitaire, brilliant, bort, jager
Nearby words
- cortázar,
- cortázar, julio,
- cortés,
- cortés, hernando,
- corumbá,
- corunna,
- coruscant,
- coruscate,
- coruscating,
- coruscation
Origin of corundum
1720–30; < Tamil kuruntam; akin to Sanskrit kuruvinda ruby
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for corundum
corundum
/ (kəˈrʌndəm) /
noun
a white, grey, blue, green, red, yellow, or brown mineral, found in metamorphosed shales and limestones, in veins, and in some igneous rocks. It is used as an abrasive and as gemstone; the red variety is ruby, the blue is sapphire. Composition: aluminium oxide. Formula: Al 2 O 3 . Crystal structure: hexagonal (rhombohedral)
Word Origin for corundum
C18: from Tamil kuruntam; related to Sanskrit kuruvinda ruby
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
corundum
"very hard mineral," 1728, from Anglo-Indian, from Tamil kurundam "ruby sapphire" (Sanskrit kuruvinda), of unknown origin.
Online Etymology Dictionary, © 2010 Douglas Harper
corundum
[ kə-rŭn′dəm ]
An extremely hard mineral occurring in many colors, either as shapeless grains or as rhombohedral crystals. It also occurs in gem varieties such as ruby and sapphire and in a dark-colored variety that is used for polishing and scraping. Corundum is found in igneous and carbonate rocks. Chemical formula: Al2O3.
The American Heritage® Science Dictionary
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