United Mexican States vs Bay of Campeche

United Mexican States and Bay of Campeche both are nouns.

Word	Noun	Adjective	Verb	Adverb
United Mexican States	Yes	No	No	No
Bay of Campeche	Yes	No	No	No

United Mexican States (noun)	Bay of Campeche (noun)
a republic in southern North America; became independent from Spain in 1810	a part of the Gulf of Mexico to the west of Yucatan