go–between

1 one that carries a message or does an errand I won't act as go-between between you and your ex Synonyms courier, express [British], go-between, page, runnerRelated Words forerunner, harbinger, herald; agent, ambassador, delegate, deputy, emissary, envoy, representative; bearer, carrier, deliveryman, letter carrier, mail carrier, mailman

2 one who works with opposing sides in order to bring about an agreement acted as go-between for the two warring nations during the peace process Synonyms broker, buffer, conciliator, go-between, honest broker, interceder, intercessor, intermediary, intermediate, interposer, middleman, peacemakerRelated Words troubleshooter; moderator; bargainer, negotiant, negotiator; appeaser, pacificator, pacifier, reconciler; agent, attorney, deputy, factor, procurator, proxy; liaison, medium; ambassador, emissary, envoy, legate, messenger; delegate, representative; busybody, interferer, meddler; arbiter, arbitrator, judge, referee, umpire; adviser (also advisor), counselor (or counsellor)