North Island vs New Zealand Islands

North Island and New Zealand Islands both are nouns.

Word	Noun	Adjective	Verb	Adverb
North Island	Yes	No	No	No
New Zealand Islands	Yes	No	No	No

North Island (noun)	New Zealand Islands (noun)
the smaller but more populous of two main islands of New Zealand; separated from South Island by Cook Strait	North Island and South Island and adjacent small islands in the South Pacific