malignant /məˈlɪgnənt/ adjective Learner's definition of MALIGNANT
[more malignant; most malignant]
1
medical : very serious and dangerous : tending or likely to grow and spread in a rapid and uncontrolled way that can cause death恶性的;致命的 — opposite benign 2
formal : very evil恶毒的;恶意的