Hawaii vs Hawaii Island

Hawaii and Hawaii Island both are nouns.

Word	Noun	Adjective	Verb	Adverb
Hawaii	Yes	No	No	No
Hawaii Island	Yes	No	No	No

As nouns, Hawaii and Hawaii Island are synonyms defined as:

Hawaii and Hawaii Island: the largest and southernmost of the Hawaii islands; has several volcanic peaks

Hawaii (noun)	Hawaii Island (noun)
a state in the United States in the central Pacific on the Hawaiian Islands	the largest and southernmost of the Hawaii islands; has several volcanic peaks
the largest and southernmost of the Hawaii islands; has several volcanic peaks