Pearl Harbor vs harbor

Pearl Harbor and harbor both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pearl Harbor	Yes	No	No	No
harbor	Yes	No	Yes	No

Pearl Harbor (noun)	harbor (noun)
a harbor on Oahu to the west of Honolulu; location of a United States naval base that was attacked by the Japanese on 7 Dec 1941	a place of refuge and comfort and security
	a sheltered port where ships can take on or discharge cargo

Pearl Harbor (verb)	harbor (verb)
	maintain (a theory, thoughts, or feelings)
	hold back a thought or feeling about
	keep in one's possession; of animals
	secretly shelter (as of fugitives or criminals)