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.
Nearby words
cortot, cortázar, cortés, cortés, hernando, corumbá, corundum, corunna, coruscant, coruscate, coruscation, coruña
Origin of corundum
1720–30; < Tamil kuruntam; akin to Sanskrit kuruvinda ruby
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Examples from the Web for corundum
British Dictionary definitions 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
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Science definitions for corundum
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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