Youngster n. : A young person; a youngling; a lad.

Example:
You’re explaining to a Youngster at the seashore why the water is cyan colored.?

Taxonomy
youngster, Encyclopedia, young person, dictionary, Youngstown, thesaurus browser, online dictionary, young child, m/f, synonyms, antonyms, Translations, Free Online Dictionary, child prodigy, youngness, English dictionary, tiddler, free online English dictionary.

Defination from the web:
youngster in the Online Dictionary. Meaning of youngster. Pronunciation of youngster. Translations of youngster. youngster synonyms, youngster antonyms. ... once it occurred to Mills that this eccentric youngster was the very person for what the legitimist sympathizers ...