sully vs darken

sully and darken both are verbs.

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

As verbs, darken is a hyponym of sully; that is, darken is a word with a more specific, narrower meaning than sully:

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

sully (verb)	darken (verb)
charge falsely or with malicious intent; attack the good name and reputation of someone	become dark or darker
make dirty or spotty, as by exposure to air; also used metaphorically	make dark or darker
place under suspicion or cast doubt upon	tarnish or stain