Pennsylvania vs Keystone State

Pennsylvania and Keystone State both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pennsylvania	Yes	No	No	No
Keystone State	Yes	No	No	No

As nouns, Pennsylvania and Keystone State are synonyms defined as:

Pennsylvania and Keystone State: a Mid-Atlantic state; one of the original 13 colonies, with capital Harrisburg

Other synonyms of Pennsylvania include Pa., PA.

Pennsylvania (noun)	Keystone State (noun)
a university in Philadelphia, Pennsylvania	a Mid-Atlantic state; one of the original 13 colonies, with capital Harrisburg
a Mid-Atlantic state; one of the original 13 colonies, with capital Harrisburg
one of the British colonies that formed the United States, with capital Philadelphia