sully vs tarnish

sully is not a noun while tarnish is a noun.

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

As verbs, sully and tarnish are synonyms defined as:

sully and tarnish: make dirty or spotty, as by exposure to air; also used metaphorically

Other synonyms of sully include defile, maculate, stain.

sully (noun)	tarnish (noun)
	discoloration of metal surface caused by oxidation

sully (verb)	tarnish (verb)
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
make dirty or spotty, as by exposure to air; also used metaphorically
place under suspicion or cast doubt upon