physicist vs Sir William Crookes

physicist and Sir William Crookes both are nouns.

Word	Noun	Adjective	Verb	Adverb
physicist	Yes	No	No	No
Sir William Crookes	Yes	No	No	No

physicist (noun)	Sir William Crookes (noun)
a scientist trained in physics	English chemist and physicist; discovered thallium; invented the radiometer and studied cathode rays (1832-1919)