1.  malignance(n = noun.state) malignancy - (medicine) a malignant state; progressive and resistant to treatment and tending to cause death;
is a kind of disease
has parts: cancer cell
has particulars: malignant neoplasm, malignant tumor, metastatic tumor
Derived form adjective malignant₁

2.  malignance(n = noun.attribute) malignancy, malignity - quality of being disposed to evil; intense ill will;
is a kind of evil, evilness

1.  The state or quality of being malignant; extreme malevolence; bitter enmity; malice; disposition toward evil; intense ill will; as, malignancy of heart. [1913 Webster]

2.  Unfavorableness; evil nature. [1913 Webster]
"The malignancy of my fate might perhaps distemner yours." [1913 Webster]

3.  Virulence; tendency to a fatal issue; as, the malignancy of an ulcer or of a fever. [1913 Webster]

4.  A cancerous tumor that is spreading beyond the point of origin. [WordNet 1.5]

5.  The state of being a malignant. [1913 Webster]