mod·​er·​a·​tor | \ ˈmä-də-ˌrā-tər How to pronounce moderator (audio) \

Definition of moderator

1 : one who arbitrates : mediator
2 : one who presides over an assembly, meeting, or discussion: such as
a : the presiding officer of a Presbyterian governing body
b : the nonpartisan presiding officer of a town meeting
c : the chairman of a discussion group
3 : a substance (such as graphite) used for slowing neutrons in a nuclear reactor

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Other Words from moderator

moderatorship \ -​ˌship How to pronounce moderatorship (audio) \ 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

The event will be hosted by group moderator and Traveler community editor Megan Spurrell and Traveler west coast editor Rebecca Misner, and is open to anyone who self-identifies as a woman. Condé Nast Traveler, "Women Who Travel Meetup: San Francisco, Here We Come," 2 Nov. 2018 Labor protections for moderators: Content moderation at large platforms depends on crowdworkers, either internal to the company or contracted through third-party temporary services. Tarleton Gillespie, WIRED, "How Social Networks Set the Limits of What We Can Say Online," 26 June 2018 The company touts a combination of human moderators and technology filters to detect attempted abuse. Andrea Fuller, WSJ, "How Companies Secretly Boost Their Glassdoor Ratings," 22 Jan. 2019 Comic-Con switch-up Yvette Nicole Brown is set to replace Chris Hardwick as moderator at AMC’s Comic-Con panels this year. Christina Schoellkopf,, "Hashtag Highlights: Comic-Con swap, Jay-Z becomes a meme," 6 July 2018 Writer Neville Wakefield, who served as moderator, said that a goal of the conversations was to bring together people from different disciplines, and that San Francisco, where so many worlds converge, was an appropriate venue. Maghan Mcdowell, San Francisco Chronicle, "Cartier’s boldface foray into SF designed to dazzle," 13 Apr. 2018 Facebook hires thousands of moderators around the world to determine if posts violate its policy on appropriate content. Gerren Keith Gaynor, Fox News, "Ex-Facebook content moderator claims disturbing images gave her PTSD; sues," 25 Sep. 2018 Almost immediately, one of the moderators expressed a concern that echoed my thoughts: Are people going to start feeling fatigued by the conversation? Susanna Fogel, Glamour, "The Spy Who Dumped Me," 3 Aug. 2018 The social-media giant is deploying AI and thousands of moderators to fight bad content. Polina Marinova, Fortune, "Term Sheet -- Friday, May 25," 25 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'moderator.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of moderator

circa 1560, in the meaning defined at sense 1

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Statistics for moderator

Last Updated

18 Mar 2019

Look-up Popularity

Time Traveler for moderator

The first known use of moderator was circa 1560

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English Language Learners Definition of moderator

: someone who leads a discussion in a group and tells each person when to speak : someone who moderates a meeting or discussion


mod·​er·​a·​tor | \ ˈmäd-ə-ˌrāt-ər How to pronounce moderator (audio) \

Medical Definition of moderator

: a substance (as graphite, deuterium in heavy water, or beryllium) used for slowing down neutrons in a nuclear reactor

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Comments on moderator

What made you want to look up moderator? Please tell us where you read or heard it (including the quote, if possible).


grandiloquent, ostentatious, or bombastic

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