hill vs Seven Hills of Rome

hill and Seven Hills of Rome both are nouns.

Word	Noun	Adjective	Verb	Adverb
hill	Yes	No	Yes	No
Seven Hills of Rome	Yes	No	No	No

hill (noun)	Seven Hills of Rome (noun)
(baseball) the slight elevation on which the pitcher stands	the hills on which the ancient city of Rome was built
structure consisting of an artificial heap or bank usually of earth or stones
a local and well-defined elevation of the land

hill (verb)	Seven Hills of Rome (verb)
form into a hill