ma·lig·nan·cy 
/məˈlɪgnənsi/ noun
plural ma·lig·nan·cies /məˈlɪgnənsi/ noun 1 [noncount] medical + formal : a malignant quality or state
▪ the malignancy of the tumor 2 [count] medical : a tumor that is malignant
▪ The test revealed a malignancy in the patient's chest.
▪ the malignancy of the tumor
▪ The test revealed a malignancy in the patient's chest.
