What is the meaning of moderator in bengali?

Meaning(s):

1. any substance used to slow down neutrons in nuclear reactors
2. in the Presdyterian church, the officer who presides over a synod or general assembly
3. someone who presides over a forum or debate
4. someone who mediates disputes and attempts to avoid violence
5. mitigator
6. धर्माधिकारी = Moderator A religious leader in the presbyterian church who is in charge of the church council
7. मध्यस्थ A person whose job is to help the two sides in a dispute to reach an agreement
8. परीक्षा नियंत्रक A person whose job is to make sure that an exam is marked fairly
9. सभापति A person whose job is to make sure that a discussion or a debate is fair