farm boy vs boy

farm boy and boy both are nouns.

Word	Noun	Adjective	Verb	Adverb
farm boy	Yes	No	No	No
boy	Yes	No	No	No

As nouns, boy is a hypernym of farm boy; that is, boy is a word with a broader meaning than farm boy:

Other hypernyms of farm boy include male child.

farm boy (noun)	boy (noun)
a boy who has grown up on a farm	a youthful male person
	(ethnic slur) offensive and disparaging term for Black man
	a friendly informal reference to a grown man
	a male human offspring