mod·​er·​a·​tor | \ ˈmä-də-ˌrā-tər \

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 \ 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

Wong, the former r/SkincareAddiction moderator, says people sometimes fall for false grails. Cheryl Wischhover, Vox, "The “best” lipstick probably won’t change your life — but the search for it can," 12 Dec. 2018 Later in the podcast, moderator Edie Lush shared some statistics that expose the reality of just how common modern day slavery is. Kara Thompson, Town & Country, "Princess Eugenie Speaks Out About Her Mission to End Modern Slavery," 4 Sep. 2018 Reinhart has worked as a coach, teacher, mentor, campus minister, assistant principal, athletic director and student council moderator. Shelby Dermer,, "St. Xavier names Brian Reinhart from Chaminade Julienne as new athletic director," 12 Apr. 2018 He was joined by director Jorma Taccone, moderator Ramin Setoodeh from Variety, and was nearly upstaged by Haddish. Cary Darling, Houston Chronicle, "Tracy Morgan makes a big comeback at SXSW," 13 Mar. 2018 According to Zenga, the Blacklist’s moderator did not respond to his inquiries via email or direct message. Emilia Petrarca, The Cut, "Fashion’s ‘Blacklist’ Has Been Taken Down," 6 Mar. 2018 On social media there are powerlifters with Nazi tattoos and wearing MAGA hats, and even the comments on powerlifting women forums were inflammatory when the moderators reposted stories of harassment. Casey Johnston, SELF, "Ask a Swole Woman: How Can I Find Safe and Inclusive Gyms?," 23 Oct. 2018 Until very recently, the platform — which is the biggest on the market — did not hire any moderators to keep Steam’s forums clean. Patricia Hernandez, The Verge, "The game store that outshines Steam by staying small and weird," 29 Nov. 2018 Most of the Groups have moderators, whereas Twitter is very much more this kind of roiling crowd that’s always angry about something. Recode Staff, Recode, "Full transcript: Data for Democracy policy head Renée DiResta answers disinformation questions on Too Embarrassed to Ask," 14 July 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

7 Jan 2019

Look-up Popularity

Time Traveler for moderator

The first known use of moderator was circa 1560

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More Definitions for moderator



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 \

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).


someone who never drinks alcohol

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