fuller vs working man

fuller and working man both are nouns.

Word	Noun	Adjective	Verb	Adverb
fuller	Yes	No	No	No
working man	Yes	No	No	No

As nouns, working man is a hypernym of fuller; that is, working man is a word with a broader meaning than fuller:

fuller: a workman who fulls (cleans and thickens) freshly woven cloth for a living
working man: an employee who performs manual or industrial labor

Other hypernyms of fuller include working person, workingman, workman.

fuller (noun)	working man (noun)
a workman who fulls (cleans and thickens) freshly woven cloth for a living	an employee who performs manual or industrial labor