free zone vs free port

free zone and free port both are nouns.

Word	Noun	Adjective	Verb	Adverb
free zone	Yes	No	No	No
free port	Yes	No	No	No

As nouns, free zone and free port are synonyms defined as:

free zone and free port: an area adjoining a port where goods that are intended for reshipment can be received and stored without payment of duties

free zone (noun)	free port (noun)
an area adjoining a port where goods that are intended for reshipment can be received and stored without payment of duties	an area adjoining a port where goods that are intended for reshipment can be received and stored without payment of duties
	a port open on equal terms to all commercial vessels