[ma.lig.nant] adj [LL malignant-, malignans, prp. of malignari] (ca. 1545) 1 a obs: malcontent, disaffected b: evil in nature, influence, or effect: injurious c: passionately and relentlessly malevolent: aggressively malicious
2: tending to produce death or deterioration "~ malaria"; esp: tending to infiltrate, metastasize, and terminate fatally "~ tumor" -- ma.lig.nant.ly adv