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 \ ˈmä-​də-​ˌrā-​tər-​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

Los Angeles Times reporter Tre-Vell Anderson served as the moderator. Chris Gardner, The Hollywood Reporter, "WME's Endeavor Content Commits to GLAAD's Inclusion Goal," 22 May 2018 Videos that are flagged, which account for a large percentage of removed content, according to Pichai, are then reviewed by the algorithm or a human moderator. Julia Alexander, The Verge, "Google still has no answers for YouTube’s biggest problem," 11 Dec. 2018 Obama’s Becoming tour will include stops across the nation and guest moderators including Oprah Winfrey and Reese Witherspoon. Aja Romano, Vox, "Michelle Obama “leans in” better than anyone. She just rejected the idea that it works.," 3 Dec. 2018 Pallotta is also a former Planning Board chairman and town moderator, and a current Plymouth County Commissioner. John Laidler,, "Five-way race for 2 Selectmen seats tops Hanover ticket," 4 May 2018 Audience members were very confused as the panel and moderator tried to keep the event rolling. Carly Mallenbaum, USA TODAY, "'Westworld' is latest panel to be killed by fan questions: Here are a few others," 22 Apr. 2018 Reddit's MakeupAddiction subreddit has always been a great source of look inspiration, moderator drama, and product recommendations — especially affordable product recommendations. Marci Robin, Allure, "I Just Found Out About This $1 Matte Liquid Lipstick on Reddit, and Now I'm Obsessed," 25 Mar. 2019 On Wednesday night, the former first lady stepped on stage to greet Sarah Jessica Parker, who served as the moderator for the evening. Marina Liao, Marie Claire, "Michelle Obama Wore a Pair of Glittery Balenciaga Boots for the Last Stop on Her 'Becoming' Tour," 20 Dec. 2018 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

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

13 May 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).


a sum of money that is sent as a payment

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