smudge vs slur

smudge and slur both are nouns.

Word	Noun	Adjective	Verb	Adverb
smudge	Yes	No	Yes	No
slur	Yes	No	Yes	No

As nouns, smudge and slur are synonyms defined as:

Other synonyms of smudge include blot, daub, smear, smirch, spot.

smudge (noun)	slur (noun)
a blemish made by dirt	a blemish made by dirt
a smoky fire to drive away insects	a disparaging remark
	(music) a curved line spanning notes that are to be played legato

smudge (verb)	slur (verb)
make a smudge on; soil by smudging	become vague or indistinct
	utter indistinctly
	speak disparagingly of; e.g., make a racial slur
	play smoothly or legato