monetary system vs medium of exchange

monetary system and medium of exchange both are nouns.

Word	Noun	Adjective	Verb	Adverb
monetary system	Yes	No	No	No
medium of exchange	Yes	No	No	No

As nouns, monetary system and medium of exchange are synonyms defined as:

monetary system and medium of exchange: anything that is generally accepted as a standard of value and a measure of wealth in a particular country or region

monetary system (noun)	medium of exchange (noun)
anything that is generally accepted as a standard of value and a measure of wealth in a particular country or region	anything that is generally accepted as a standard of value and a measure of wealth in a particular country or region