Panama Canal Zone vs Canal Zone

Panama Canal Zone and Canal Zone both are nouns.

Word	Noun	Adjective	Verb	Adverb
Panama Canal Zone	Yes	No	No	No
Canal Zone	Yes	No	No	No

As nouns, Panama Canal Zone and Canal Zone are synonyms defined as:

Panama Canal Zone and Canal Zone: a zone consisting of a strip of land across the Isthmus of Panama that contains the Panama Canal

Panama Canal Zone (noun)	Canal Zone (noun)
a zone consisting of a strip of land across the Isthmus of Panama that contains the Panama Canal	a zone consisting of a strip of land across the Isthmus of Panama that contains the Panama Canal