juvenile vs adolescent

juvenile and adolescent both are nouns.

Word	Noun	Adjective	Verb	Adverb
juvenile	Yes	Yes	No	No
adolescent	Yes	Yes	No	No

As adjectives, juvenile and adolescent are synonyms defined as:

Other synonyms of juvenile include jejune, puerile.

As nouns, adolescent is a hyponym of juvenile; that is, adolescent is a word with a more specific, narrower meaning than juvenile:

juvenile (noun)	adolescent (noun)
a young person, not fully developed	a juvenile between the onset of puberty and maturity

juvenile (adjective)	adolescent (adjective)
of or relating to or characteristic of or appropriate for children or young people	relating to or peculiar to or suggestive of an adolescent
displaying or suggesting a lack of maturity	in the state of development between puberty and maturity
	displaying or suggesting a lack of maturity
	being of the age 13 through 19