South American country vs South American nation

South American country and South American nation both are nouns.

Word	Noun	Adjective	Verb	Adverb
South American country	Yes	No	No	No
South American nation	Yes	No	No	No

As nouns, South American country and South American nation are synonyms defined as:

South American country and South American nation: any one of the countries occupying the South American continent

South American country (noun)	South American nation (noun)
any one of the countries occupying the South American continent	any one of the countries occupying the South American continent