schoolgirlish vs young

schoolgirlish is not a noun while young is a noun.

Word	Noun	Adjective	Verb	Adverb
schoolgirlish	No	Yes	No	No
young	Yes	Yes	No	No

schoolgirlish (noun)	young (noun)
	any immature animal
	young people collectively

schoolgirlish (adjective)	young (adjective)
befitting or characteristic of a young girl	(used of living things especially persons) in an early period of life or development or growth
	(of crops) harvested at an early stage of development; before complete maturity
	not tried or tested by experience
	being in its early stage
	suggestive of youth; vigorous and fresh