Available Definitions:
1) n. - The state or quality of being malignant; extreme malevolence; bitter enmity; malice; as, malignancy of heart.
2) n. - Unfavorableness; evil nature.
3) n. - Virulence; tendency to a fatal issue; as, the malignancy of an ulcer or of a fever.
4) n. - The state of being a malignant.