Samoa vs Western Samoa

Samoa and Western Samoa both are nouns.

Word	Noun	Adjective	Verb	Adverb
Samoa	Yes	No	No	No
Western Samoa	Yes	No	No	No

As nouns, Samoa and Western Samoa are synonyms defined as:

Samoa and Western Samoa: a constitutional monarchy on the western part of the islands of Samoa in the South Pacific

Other synonyms of Samoa include Independent State of Samoa, Samoa i Sisifo.

Samoa (noun)	Western Samoa (noun)
a constitutional monarchy on the western part of the islands of Samoa in the South Pacific	a constitutional monarchy on the western part of the islands of Samoa in the South Pacific
a group of volcanic islands in the South Pacific midway between Hawaii and Australia; its climate and scenery and Polynesian culture make it a popular tourist stop