intercessor vs intermediator

intercessor and intermediator both are nouns.

Word	Noun	Adjective	Verb	Adverb
intercessor	Yes	No	No	No
intermediator	Yes	No	No	No

As nouns, intercessor and intermediator are synonyms defined as:

intercessor and intermediator: a negotiator who acts as a link between parties

Other synonyms of intercessor include go-between, intermediary, mediator.

intercessor (noun)	intermediator (noun)
a negotiator who acts as a link between parties	a negotiator who acts as a link between parties