malignant

a.	1.	Disposed to do harm, inflict suffering, or cause distress; actuated by extreme malevolence or enmity; virulently inimical; bent on evil; malicious. A malignant and a turbaned Turk. - Shak.
	2.	Characterized or caused by evil intentions; pernicious. Some malignant power upon my life. - Shak. Something deleterious and malignant as his touch. - Hawthorne.
	3.	(Med.) Tending to produce death; threatening a fatal issue; virulent; as, malignant diphtheria. Malignant pustule (Med.) a very contagious disease produced by infection of subcutaneous tissues with the bacterium Bacillus anthracis. It is transmitted to man from animals and is characterized by the formation, at the point of reception of the infection, of a vesicle or pustule which first enlarges and then breaks down into an unhealthy ulcer. It is marked by profound exhaustion and often fatal. The disease in animals is called charbon; in man it is called cutaneous anthrax, and formerly was sometimes called simply anthrax.
n.	1.	A man of extreme enmity or evil intentions.
	2.	(Eng. Hist.) One of the adherents of Charles I. or Charles II.; - so called by the opposite party.

Adj.	1.	malignant - dangerous to health; characterized by progressive and uncontrolled growth (especially of a tumor) Antonyms: benign - not dangerous to health; not recurrent or progressive (especially of a tumor)
	2.	malignant - extremely malevolent or malicious; "the malignant tongues of gossipers" Synonyms: malevolent

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