Malignance is a medical term that's most often used to talk about a malignant — or cancerous — tumor. It's bad news when a surgeon discovers a malignance in a patient.
You can use malignance when you talk about cancer, but you can also use it to mean the quality of being evil or of wishing ill will on someone. If a student feels malignance toward his entire class, he dislikes them all. You might wonder if war and other conflicts can ever be ended as long as groups of people feel such malignance toward other groups. The root of malignance is the Late Latin word malignantem, "injure maliciously."