buster vs nestling

buster and nestling both are nouns.

Word	Noun	Adjective	Verb	Adverb
buster	Yes	No	No	No
nestling	Yes	No	No	No

As nouns, nestling is a hypernym of buster; that is, nestling is a word with a broader meaning than buster:

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

buster (noun)	nestling (noun)
a person (or thing) that breaks up or overpowers something	young bird not yet fledged
a person who breaks horses	a young person of either sex
a robust child
an informal form of address for a man
a person born in the generation following the baby boom when the birth rate fell dramatically