: any binary compound of boron and carbon; especially : a refractory shiny black crystalline solid B4C ranking next to the diamond in hardness made usually by heating boric oxide and coke in an electric furnace and used chiefly as powdered and molded abrasives
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Chem.
a black, crystalline, extremely hard, water-insoluble solid, B4C, used chiefly as a moderator in nuclear reactors, as an abrasive, and as a refractory.
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boron carbide,
an extremely hard, crystalline compound, used in cutting tools. Formula: B4C
Useful english dictionary. 2012.