corundum Syllabification: (co·run·dum)Pronunciation: /kəˈrəndəm/Definition of corundum noun extremely hard aluminum oxide, used as an abrasive. Ruby and sapphire are varieties of corundum. Origin: early 18th century: from Tamil kuruntam and Telugu kuruvindamcorundum in other Oxford dictionaries Definition of corundum in the British & World English dictionary
