skinny vs tight fitting

skinny is a noun but tight fitting is not a noun.

Word	Noun	Adjective	Verb	Adverb
skinny	Yes	Yes	No	No
tight fitting	No	Yes	No	No

As adjectives, skinny and tight fitting are synonyms defined as:

Other synonyms of skinny include tight-fitting, tightfitting, tightly fitting.

skinny (noun)	tight fitting (noun)
confidential information about a topic or person

skinny (adjective)	tight fitting (adjective)
of or relating to or resembling skin	fitting snugly
giving or spending with reluctance
being very thin
fitting snugly