boy vs male offspring

boy and male offspring both are nouns.

Word	Noun	Adjective	Verb	Adverb
boy	Yes	No	No	No
male offspring	Yes	No	No	No

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

Other hypernyms of boy include man-child.

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