Northern Mariana Islands vs Saipan

Northern Mariana Islands and Saipan both are nouns.

Word	Noun	Adjective	Verb	Adverb
Northern Mariana Islands	Yes	No	No	No
Saipan	Yes	No	No	No

Northern Mariana Islands (noun)	Saipan (noun)
a self-governing territory comprising all of the Mariana Islands except Guam	US forces captured the island from the Japanese in July 1944; it was an important air base until the end of World War II
	the largest island in the Northern Marianas and the administrative center of the commonwealth of the Northern Mariana Islands in union with the United States