young bird vs chick

young bird and chick both are nouns.

Word	Noun	Adjective	Verb	Adverb
young bird	Yes	No	No	No
chick	Yes	No	No	No

As nouns, chick is a hyponym of young bird; that is, chick is a word with a more specific, narrower meaning than young bird:

Other hyponyms of young bird include fledgeling, fledgling, baby bird, nestling, eaglet, biddy, cygnet.

young bird (noun)	chick (noun)
a bird that is still young	young bird especially of domestic fowl
	informal terms for a (young) woman