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 of course, last but not least is our moderator. —Outside Online, 21 Jan. 2026

After Federer escaped the clutches of moderator and media, a crowd of fans assembled below an overhanging balcony, taking pictures of him doing his next interview. —Owen Lewis, New York Times, 16 Jan. 2026

The moderator, Aviva Klompas, pointed out that many in the room may be concerned about the Democratic Party’s support for Israel amid the party’s internal division over issues like the war in Gaza. —Lauren Costantino, Miami Herald, 16 Jan. 2026

During a panel hosted by sustainability moderator Merle Becker, industry heavyweights explored how the sector’s transformation—from artificial intelligence (AI) and automation to sustainable materials and digital development processes—is becoming a strategic resource. —Alexandra Harrell, Sourcing Journal, 15 Jan. 2026

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