moderator

noun

mod·​er·​a·​tor ˈmä-də-ˌrā-tər How to pronounce moderator (audio)
plural moderators
Synonyms of moderatornext
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 How to pronounce moderator (audio)
noun

Synonyms of moderator

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Kansas’ junior Republican senator spent roughly 30 minutes answering questions from a Greater Topeka Chamber of Commerce moderator. — Matthew Kelly, Kansas City Star, 17 Oct. 2026 Bass’ barrages got to Raman more than a few times, leading her to talk over the NBC and Telemundo moderators or even shush them. — Lorraine Ali, Los Angeles Times, 14 Oct. 2026 Amitav Ghosh, author of The Ibis Trilogy, served as the evening’s moderator. — Literary Hub, 13 Oct. 2026 Excessive false positives also overwhelmed the human moderators trying to detect dangerous accounts. — Vicky Nguyen, NBC news, 13 Oct. 2026 See All Example Sentences for moderator

Word History

First Known Use

circa 1560, in the meaning defined at sense 2

Time Traveler
The first known use of moderator was circa 1560

Rhymes for moderator

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Browse Nearby Words

moderato
moderator
moderatorial
See all Nearby Words

Cite this Entry

“Moderator.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/moderator. Accessed 19 Oct. 2026.

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Kids Definition

moderator

noun
mod·​er·​a·​tor ˈmäd-ə-ˌrāt-ər How to pronounce moderator (audio)
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 How to pronounce moderator (audio)
: a substance (as graphite, deuterium in heavy water, or beryllium) used for slowing down neutrons in a nuclear reactor

More from Merriam-Webster on moderator

Britannica.com: Encyclopedia article about moderator

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