Cancer - This from Wikipedia
Cancer /ˈkænsər/ ( listen), known medically as a malignant neoplasm, is a broad group of various diseases, all involving unregulated cell growth. In cancer,cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the body through the lymphatic system or bloodstream.Malignancy
Malignancy (from Malign from Latin roots male "badly" + -gnus "born") is the tendency of a medical condition, especially tumors, to become progressively worse and to potentially result in death. Malignancy in cancers is characterized by anaplasia, invasiveness, and metastasis. Malignant is a corresponding adjectival medical term used to describe a severe and progressively worsening disease. The term is most familiar as a description of cancer. A malignant tumor may be contrasted with a non-cancerous benign tumor in that a malignancy is not self-limited in its growth, is capable of invading into adjacent tissues, and may be capable of spreading to distant tissues (metastasizing), while a benign tumor has none of those properties. Malignant tumor is synonymous with cancer. Uses of "malignant" in oncology:
Completely shot down all systems and kill the person that is cancer!