Rachmaninov vs composer

Rachmaninov and composer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Rachmaninov	Yes	No	No	No
composer	Yes	No	No	No

Rachmaninov (noun)	composer (noun)
composer and piano virtuoso born in Russia (1873-1943)	someone who composes music, usually as a profession