Hall vs astronomer

Hall and astronomer both are nouns.

Word	Noun	Adjective	Verb	Adverb
Hall	Yes	No	No	No
astronomer	Yes	No	No	No

Hall (noun)	astronomer (noun)
United States astronomer who discovered Phobos and Deimos (the two satellites of Mars) (1829-1907)	a physicist who studies astronomy
United States explorer who led three expeditions to the Arctic (1821-1871)
United States chemist who developed an economical method of producing aluminum from bauxite (1863-1914)
United States child psychologist whose theories of child psychology strongly influenced educational psychology (1844-1924)
English writer whose novel about a lesbian relationship was banned in Britain for many years (1883-1943)