Spanish vs Romance language

Spanish and Romance language both are nouns.

Word	Noun	Adjective	Verb	Adverb
Spanish	Yes	Yes	No	No
Romance language	Yes	No	No	No

As nouns, Romance language is a hypernym of Spanish; that is, Romance language is a word with a broader meaning than Spanish:

Spanish: the Romance language spoken in most of Spain and the countries colonized by Spain
Romance language: the group of languages derived from Latin

Other hypernyms of Spanish include Latinian language, Romance.

Spanish (noun)	Romance language (noun)
the Romance language spoken in most of Spain and the countries colonized by Spain	the group of languages derived from Latin
the people of Spain

Spanish (adjective)	Romance language (adjective)
of or relating to or characteristic of Spain or the people of Spain