metropolis vs Bombay

metropolis and Bombay both are nouns.

Word	Noun	Adjective	Verb	Adverb
metropolis	Yes	No	No	No
Bombay	Yes	No	No	No

metropolis (noun)	Bombay (noun)
people living in a large densely populated municipality	a city in western India just off the coast of the Arabian Sea; India's 2nd largest city (after Calcutta); has the only natural deep-water harbor in western India
a large and densely populated urban area; may include several independent administrative districts