Cape Sable vs Cape Sable Island

Cape Sable and Cape Sable Island both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cape Sable	Yes	No	No	No
Cape Sable Island	Yes	No	No	No

As nouns, Cape Sable and Cape Sable Island are synonyms defined as:

Cape Sable and Cape Sable Island: a promontory on the far southern part of Nova Scotia

Cape Sable (noun)	Cape Sable Island (noun)
a promontory on the far southern part of Nova Scotia	a promontory on the far southern part of Nova Scotia
a cape at the southwest tip of Florida; the southernmost part of the United States mainland