United Mexican States vs Buena Vista

United Mexican States and Buena Vista both are nouns.

Word	Noun	Adjective	Verb	Adverb
United Mexican States	Yes	No	No	No
Buena Vista	Yes	No	No	No

United Mexican States (noun)	Buena Vista (noun)
a republic in southern North America; became independent from Spain in 1810	a pitched battle in the Mexican War in 1847; United States forces under Zachary Taylor defeated the Mexican forces under Santa Anna at a locality in northern Mexico