London vs author

London and author both are nouns.

Word	Noun	Adjective	Verb	Adverb
London	Yes	No	No	No
author	Yes	No	Yes	No

London (noun)	author (noun)
the capital and largest city of England; located on the Thames in southeastern England; financial and industrial and cultural center	writes (books or stories or articles or the like) professionally (for pay)
United States writer of novels based on experiences in the Klondike gold rush (1876-1916)	someone who originates or causes or initiates something

London (verb)	author (verb)
	be the author of