malign vs sully

malign is an adjective but sully is not an adjective.

Word	Noun	Adjective	Verb	Adverb
malign	No	Yes	Yes	No
sully	No	No	Yes	No

As verbs, sully is a hypernym of malign; that is, sully is a word with a broader meaning than malign:

malign: speak unfavorably about
sully: charge falsely or with malicious intent; attack the good name and reputation of someone

Other hypernyms of malign include asperse, besmirch, calumniate, defame, denigrate, slander, smear, smirch.

malign (adjective)	sully (adjective)
evil or harmful in nature or influence
having or exerting a malignant influence

malign (verb)	sully (verb)
speak unfavorably about	charge falsely or with malicious intent; attack the good name and reputation of someone
	make dirty or spotty, as by exposure to air; also used metaphorically
	place under suspicion or cast doubt upon