me·​di·​a·​tor | \ˈmē-dē-ˌā-tər \

Definition of mediator 

1 : one that mediates especially : one that mediates between parties at variance

2 : a mediating agent in a physical, chemical, or biological process

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Examples of mediator in a Sentence

if you two cannot resolve this argument on your own, we'll have to bring in a mediator

Recent Examples on the Web

Still, Moon, who is playing something of a mediator role in the talks, was optimistic. Anna Fifield, Washington Post, "U.S. officials hold summit preparation talks despite uncertainty surrounding Trump-Kim meeting," 27 May 2018 Presiding over the session was a professional mediator, hired by the Office of Compliance. The Washington Post,, "A woman was paid $220K to secretly settle a congressional harassment claim," 15 Jan. 2018 Having a third party as a mediator, such as a geriatric-care manager, is helpful in diffusing tense situations. Kelsey Mo, azcentral, "When and how to discuss senior-housing options with aging parents," 13 July 2018 Although the 1978 Camp David talks featured two leaders — Egyptian President Anwar Sadat and Israeli Prime Minister Menachem Begin — with similar antipathy, the big difference was an empathetic mediator, Jimmy Carter. Marcus Holmes, Washington Post, "Trump canceled the summit with North Korea. Here’s the real missed opportunity.," 24 May 2018 The Palestinians say the U.S. is no longer an acceptable mediator. Aron Heller, The Seattle Times, "Pence says US embassy will move to Jerusalem by end of 2019," 22 Jan. 2018 Typically, the litigants split the mediator’s fee, which in Mr. Cohen’s case is about $500 an hour. Corinne Ramey, WSJ, "New York to Litigants: Let’s Settle Those Lawsuits," 4 July 2018 Palestinian President Mahmoud Abbas cut ties with the U.S., declaring it unfit to be the sole mediator for potential peace between Israel and Palestine. Ryan Gaydos, Fox News, "US Embassy move to Jerusalem 'national security priority,' Mnuchin says," 14 May 2018 Moon, who has been a mediator between Trump and Kim, called an emergency meeting in the middle of the night Thursday after Trump called off the June summit in a letter to Kim. James Griffiths, CNN, "South Korea's Moon: North Korea still committed to full denuclearization," 26 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mediator.' 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 mediator

14th century, in the meaning defined at sense 1

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Last Updated

14 Nov 2018

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The first known use of mediator was in the 14th century

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me·​di·​a·​tor | \ˈmēd-ē-ˌāt-ər \

Medical Definition of mediator 

: one that mediates especially : a mediating agent (as an enzyme or hormone) in a chemical or biological process substance P, a neuropeptide mediator of analgesic stimuli in peripheral sensory nerves — D. R. Robinson


me·​di·​a·​tor | \ˈmē-dē-ˌā-tər \

Legal Definition of mediator 

: one that works to effect reconciliation, settlement, or compromise between parties at variance — compare arbitrator

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by force of circumstances

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