Malaya vs West Malaysia

Malaya and West Malaysia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Malaya	Yes	No	No	No
West Malaysia	Yes	No	No	No

As nouns, Malaya and West Malaysia are synonyms defined as:

Malaya and West Malaysia: the region of Malaysia on the Malay Peninsula; shares a land border with Thailand to the north

Other synonyms of Malaya include Peninsular Malaysia.

Malaya (noun)	West Malaysia (noun)
the region of Malaysia on the Malay Peninsula; shares a land border with Thailand to the north	the region of Malaysia on the Malay Peninsula; shares a land border with Thailand to the north