chemist vs Karl Ziegler

chemist and Karl Ziegler both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemist	Yes	No	No	No
Karl Ziegler	Yes	No	No	No

chemist (noun)	Karl Ziegler (noun)
a scientist who specializes in chemistry	German chemist honored for his research on polymers (1898-1973)
a health professional trained in the art of preparing and dispensing drugs