French person vs Breton

French person and Breton both are nouns.

Word	Noun	Adjective	Verb	Adverb
French person	Yes	No	No	No
Breton	Yes	No	No	No

As nouns, Breton is a hyponym of French person; that is, Breton is a word with a more specific, narrower meaning than French person:

French person: a person of French nationality
Breton: a native or inhabitant of Brittany (especially one who speaks the Breton language)

Other hyponyms of French person include frog, Gaul, Parisian, Savoyard, Angevin, Angevine, Norman, Frenchman, Frenchwoman.

French person (noun)	Breton (noun)
a person of French nationality	a Celtic language of Brittany
	a native or inhabitant of Brittany (especially one who speaks the Breton language)