Malay Peninsula vs Malayan

Malay Peninsula and Malayan both are nouns.

Word	Noun	Adjective	Verb	Adverb
Malay Peninsula	Yes	No	No	No
Malayan	Yes	Yes	No	No

Malay Peninsula (noun)	Malayan (noun)
a peninsula in southeastern Asia occupied by parts of Malaysia and Thailand and Myanmar	a member of a people inhabiting the northern Malay Peninsula and Malaysia and parts of the western Malay Archipelago

Malay Peninsula (adjective)	Malayan (adjective)
	of or relating to or characteristic of the people or language of Malaysia and the northern Malay Peninsula and parts of the western Malay Archipelago
	of or relating to or characteristic of Malaysia