fellow vs buster

fellow and buster both are nouns.

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

As nouns, fellow and buster are synonyms defined as:

Other synonyms of fellow include dude.

fellow (noun)	buster (noun)
a boy or man	a person (or thing) that breaks up or overpowers something
a man who is the lover of a man or woman	a person who breaks horses
a friend who is frequently in the company of another	a robust child
a person who is member of one's class or profession	an informal form of address for a man
an informal form of address for a man	a person born in the generation following the baby boom when the birth rate fell dramatically
a member of a learned society
one of a pair