Alexander Prokhorov vs physicist

Alexander Prokhorov and physicist both are nouns.

Word	Noun	Adjective	Verb	Adverb
Alexander Prokhorov	Yes	No	No	No
physicist	Yes	No	No	No

Alexander Prokhorov (noun)	physicist (noun)
Russian physicist whose research into ways of moving electrons around atoms led to the development of masers and lasers for producing high-intensity radiation (1916-2002)	a scientist trained in physics