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

Joy Behar has missed three consecutive episodes of The View, with moderator Whoopi Goldberg revealing a health update for the 83-year-old comedian. —Joey Nolfi, Entertainment Weekly, 12 Nov. 2025

Altra Running global brand president Jen McLaren, Vibram president and global brand chief officer Fabrizio Gamberini and Saucony vice president Ted Fitzpatrick will take part in the discussion, with FN senior digital news writer Ian Servantes serving as moderator. —Ian Servantes, Footwear News, 11 Nov. 2025

Many felt their questions about Gibb were deliberately ignored by BBC moderators. —Jake Kanter, Deadline, 11 Nov. 2025

Suarez, the event’s principal moderator, inquired of Jeff Bezos, who spent some of his childhood in the area. —Max Klaver, Miami Herald, 8 Nov. 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