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 chairman 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

• 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

The league doesn’t control r/NFL, and its social media managers have met with the page’s longtime moderators to ensure smooth cooperation. —Jacob Feldman, Sportico.com, 15 Oct. 2025

Martin gave the update while answering a question from moderator and horror author Joe Hill about the series’ status as part of a spotlight panel hosted on Saturday at New York Comic Con. —Abbey White, HollywoodReporter, 11 Oct. 2025

Rules of decorum The Enquirer and both candidates have set the debate rules with a strong emphasis on mutual respect for the candidates and moderator, and the opportunity for all attendees to be unhindered in their ability to listen and hear the candidates’ responses. —Staff, Cincinnati Enquirer, 9 Oct. 2025

When asked by moderator and podcast host Josh Horowitz if there would ever be a spinoff, Esmail took a tangent to answer the question, but wound up at the point. —Anthony D'alessandro, Deadline, 9 Oct. 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