slimness vs slightness

slimness and slightness both are nouns.

Word	Noun	Adjective	Verb	Adverb
slimness	Yes	No	No	No
slightness	Yes	No	No	No

As nouns, slimness and slightness are synonyms defined as:

Other synonyms of slimness include slenderness.

slimness (noun)	slightness (noun)
the property of an attractively thin person	slenderness
a small margin	the property of an attractively thin person
	the quality of being unimportant and petty or frivolous