blond person vs someone

blond person and someone both are nouns.

Word	Noun	Adjective	Verb	Adverb
blond person	Yes	No	No	No
someone	Yes	No	No	No

As nouns, someone is a hypernym of blond person; that is, someone is a word with a broader meaning than blond person:

blond person: a person with fair skin and hair
someone: a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential

Other hypernyms of blond person include individual, mortal, person, somebody, soul.

blond person (noun)	someone (noun)
a person with fair skin and hair	a human being; person, singular, assertive existential pronoun; pronoun, person, singular; quantifier: assertive existential