Pacific Ocean vs Japanese Archipelago

Pacific Ocean and Japanese Archipelago both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pacific Ocean	Yes	No	No	No
Japanese Archipelago	Yes	No	No	No

Pacific Ocean (noun)	Japanese Archipelago (noun)
the largest ocean in the world	a string of more than 3,000 islands to the east of Asia extending 1,300 miles between the Sea of Japan and the western Pacific Ocean