melt off vs slim

melt off is not an adjective while slim is an adjective.

Word	Noun	Adjective	Verb	Adverb
melt off	No	No	Yes	No
slim	No	Yes	Yes	No

As verbs, melt off and slim are synonyms defined as:

Other synonyms of melt off include reduce, slenderize, slim down, thin.

melt off (adjective)	slim (adjective)
	small in quantity
	being of delicate or slender build

melt off (verb)	slim (verb)
take off weight	take off weight