physicist vs Benjamin Thompson

physicist and Benjamin Thompson both are nouns.

Word	Noun	Adjective	Verb	Adverb
physicist	Yes	No	No	No
Benjamin Thompson	Yes	No	No	No

physicist (noun)	Benjamin Thompson (noun)
a scientist trained in physics	English physicist (born in America) who studied heat and friction; experiments convinced him that heat is caused by moving particles (1753-1814)