papillon vs toy spaniel

papillon and toy spaniel both are nouns.

Word	Noun	Adjective	Verb	Adverb
papillon	Yes	No	No	No
toy spaniel	Yes	No	No	No

As nouns, toy spaniel is a hypernym of papillon; that is, toy spaniel is a word with a broader meaning than papillon:

papillon: small slender toy spaniel with erect ears and a black-spotted brown to white coat
toy spaniel: a very small spaniel

papillon (noun)	toy spaniel (noun)
small slender toy spaniel with erect ears and a black-spotted brown to white coat	a very small spaniel