negotiator
[noun]
Synonyms: mediator, ambassador, delegate, diplomat, honest broker, intermediary, moderator

[TahlilGaran] English Synonym Dictionary ▲

ne‧go‧ti‧a‧tor /nɪˈɡəʊʃieɪtə $ -ˈɡoʊʃieɪtər/ noun [countable]
someone who takes part in official discussions, especially in business or politics, in order to try and reach an agreement:
the chief union negotiator

[TahlilGaran] Dictionary of Contemporary English ▲

negotiator
noun
ADJ. clever, good, skilled, tough | professional, trained | chief, principal, senior the trade union's chief negotiator
union
 ⇒ Note at JOB

[TahlilGaran] Collocations Dictionary ▲