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.
Origin of corundum
1720–30; < Tamil
kuruntam; akin to Sanskrit
kuruvinda ruby
Words nearby corundum
cortot,
cortázar,
cortés,
cortés, hernando,
corumbá,
corundum,
corunna,
coruscant,
coruscate,
coruscation,
coruña
Example sentences 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
Scientific 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.