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 noun

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.
The topics posed by the debate moderators touched on only a couple of those issues, and then too briefly to be significant. Dan Walters, Oc Register, 23 Apr. 2026 Alongside Variety moderator Marc Malkin, each panelist opened up about their journey to becoming an entrepreneur. Payton Turkeltaub, Variety, 23 Apr. 2026 Postmoderation, on the other hand, typically involves moderators getting involved once content has been flagged by users or otherwise brought to the attention of moderators. Encyclopedia Britannica, 22 Apr. 2026 Unlike similar global gatherings, Semafor World Economy is first of all a festival of news, rooted in the revelatory power of good journalism, so our reporters and guest moderators asked challenging questions and hard follow-ups in the hope of understanding how leaders see this confounding moment. Ben Smith, semafor.com, 20 Apr. 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

Browse Nearby Words

Cite this Entry

“Moderator.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/moderator. Accessed 27 Apr. 2026.

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

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster