Aleutians vs Aleutian Islands

Aleutians and Aleutian Islands both are nouns.

Word	Noun	Adjective	Verb	Adverb
Aleutians	Yes	No	No	No
Aleutian Islands	Yes	No	No	No

As nouns, Aleutians and Aleutian Islands are synonyms defined as:

Aleutians and Aleutian Islands: an archipelago in the North Pacific extending southwest from Alaska

Aleutians (noun)	Aleutian Islands (noun)
an archipelago in the North Pacific extending southwest from Alaska	an archipelago in the North Pacific extending southwest from Alaska