moderator

noun

mod·​er·​a·​tor ˈmä-də-ˌrā-tər 

plural moderators

1

: someone who presides over an assembly, meeting, or discussion: such as

a

: the chairperson of a discussion group

b

: a person who administers an online forum, chat room, or group

c

: the nonpartisan presiding officer of a town meeting

d

: the presiding officer of a Presbyterian governing body

2

: one who arbitrates : mediator

3

: a substance (such as graphite) used for slowing neutrons in a nuclear reactor

moderatorship

ˈmä-də-ˌrā-tər-ˌship 

noun

Synonyms of moderator

• chairperson
• president
• chairman
• presider

Examples of moderator in a Sentence

The moderator allowed audience members to ask the governor questions.

She acts as the moderator in our office meetings.

Recent Examples on the Web

And that’s where sitting down together (with a moderator in the room) can help. —Jenna Ryu, SELF, 16 Dec. 2025

Dayle Stevens, a Telstra data and AI executive, told moderator Jeremy Kahn that the company had a five-year strategic roadmap but realized the market was moving too fast for standard timelines. —Nick Lichtenberg, Fortune, 16 Dec. 2025

Erika Kirk took questions from guests of a town hall, with CBS News Editor-in-Chief Bari Weiss as the moderator. —Ryan Mancini, The Hill, 14 Dec. 2025

The moderator asked Chalamet what the star himself can learn from his character, Marty Mauser, an aspiring table tennis player in 1950s New York City. —Ryan Gajewski, HollywoodReporter, 6 Dec. 2025

Word History

First Known Use

circa 1560, in the meaning defined at sense 2

Rhymes for moderator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

Kids Definition

moderator

noun

mod·​er·​a·​tor ˈmäd-ə-ˌrāt-ər 

1

: one that moderates: as

a

: the leader of a Presbyterian governing body

b

: the chairperson of a town meeting

c

: the chairperson of a discussion group (as on television)

2

: a substance (as graphite) used for slowing down neutrons in a nuclear reactor

Medical Definition

moderator

noun

mod·​er·​a·​tor ˈmäd-ə-ˌrāt-ər 

: a substance (as graphite, deuterium in heavy water, or beryllium) used for slowing down neutrons in a nuclear reactor