Greater New York vs Manhattan Island

Greater New York and Manhattan Island both are nouns.

Word	Noun	Adjective	Verb	Adverb
Greater New York	Yes	No	No	No
Manhattan Island	Yes	No	No	No

Greater New York (noun)	Manhattan Island (noun)
the largest city in New York State and in the United States; located in southeastern New York at the mouth of the Hudson river; a major financial and cultural center	an island at the north end of New York Bay where the borough of Manhattan is located