[kahr-buh-ruhn-duh
m] 
| any of various abrasives or refractories of silicon carbide, fused alumina, and other materials. |
| Car·bo·run·dum (kär'bə-rŭn'dəm) A trademark used for an abrasive of silicon carbide crystals. |
Carborundum
exceedingly hard, synthetically produced crystalline compound of silicon and carbon. Its chemical formula is SiC. Since the late 19th century silicon carbide has been an important material for sandpapers, grinding wheels, and cutting tools. More recently, it has found application in refractory linings and heating elements for industrial furnaces, in wear-resistant parts for pumps and rocket engines, and in semiconducting substrates for light-emitting diodes.
Learn more about Carborundum with a free trial on Britannica.com.