bambino vs youngster

bambino and youngster both are nouns.

Word	Noun	Adjective	Verb	Adverb
bambino	Yes	No	No	No
youngster	Yes	No	No	No

As nouns, youngster is a hypernym of bambino; that is, youngster is a word with a broader meaning than bambino:

Other hypernyms of bambino include child, fry, kid, minor, nestling, nipper, shaver, small fry, tiddler, tike, tyke.

bambino (noun)	youngster (noun)
a young child who is just beginning to walk	a young person of either sex