cooperator vs pardner

cooperator and pardner both are nouns.

Word	Noun	Adjective	Verb	Adverb
cooperator	Yes	No	No	No
pardner	Yes	No	No	No

As nouns, cooperator and pardner are synonyms defined as:

cooperator and pardner: an associate in an activity or endeavor or sphere of common interest

Other synonyms of cooperator include collaborator, partner.

cooperator (noun)	pardner (noun)
an associate in an activity or endeavor or sphere of common interest	an associate in an activity or endeavor or sphere of common interest