chemist vs William Crookes

chemist and William Crookes both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemist	Yes	No	No	No
William Crookes	Yes	No	No	No

chemist (noun)	William Crookes (noun)
a scientist who specializes in chemistry	English chemist and physicist; discovered thallium; invented the radiometer and studied cathode rays (1832-1919)
a health professional trained in the art of preparing and dispensing drugs