dairyman vs fieldhand

dairyman and fieldhand both are nouns.

Word	Noun	Adjective	Verb	Adverb
dairyman	Yes	No	No	No
fieldhand	Yes	No	No	No

As nouns, fieldhand is a hypernym of dairyman; that is, fieldhand is a word with a broader meaning than dairyman:

Other hypernyms of dairyman include farm worker, farmhand, field hand.

dairyman (noun)	fieldhand (noun)
the owner or manager of a dairy	a hired hand on a farm
a man who works in a dairy