Malaya vs Peninsular Malaysia

Malaya and Peninsular Malaysia both are nouns.

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

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

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

Other synonyms of Malaya include West Malaysia.

Malaya (noun)	Peninsular 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