mediator

noun

me·​di·​a·​tor ˈmē-dē-ˌā-tər How to pronounce mediator (audio)
Synonyms of mediator
1
: one that mediates
especially : one that mediates between disputing parties
2
: a mediating agent in a physical, chemical, or biological process

Synonyms of mediator

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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
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.
Every accusation that has been thrown my way has been found unsubstantiated by the court system as well as mine and my ex-wife's court appointed mediator (who is a psychologist and mandatory reporter). — Rachel Scott, ABC News, 4 Aug. 2026 Iranian diplomats reacted positively to a plan presented by Qatari mediators to restore traffic through the Strait of Hormuz, which usually carries 20% of the world’s oil, The Wall Street Journal reported. — semafor.com, 3 Aug. 2026 Trump called off plans to strike Iran’s energy infrastructure over the weekend after Tehran and regional mediators asked to restart peace talks. — Christian Datoc, The Washington Examiner, 3 Aug. 2026 Late in March, with global energy prices soaring as Iran targeted Gulf refineries and ships crossing the Strait of Hormuz, Washington and Tehran began to exchange cease-fire proposals via Pakistan and other mediators. — Miranda Jeyaretnam, Time, 3 Aug. 2026 See All Example Sentences for mediator

Word History

First Known Use

14th century, in the meaning defined at sense 1

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

Rhymes for mediator

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Browse Nearby Words

mediatize
mediator
mediatorial
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Cite this Entry

“Mediator.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mediator. Accessed 12 Aug. 2026.

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Kids Definition

mediator

noun
me·​di·​a·​tor ˈmēd-ē-ˌāt-ər How to pronounce mediator (audio)
: one that mediates
mediatory
-ē-ə-ˌtōr-ē, 
-ˌtȯr-
adjective

Medical Definition

mediator

noun
me·​di·​a·​tor ˈmēd-ē-ˌāt-ər How to pronounce mediator (audio)
: 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

Legal Definition

mediator

noun
me·​di·​a·​tor ˈmē-dē-ˌā-tər How to pronounce mediator (audio)
: one that works to effect reconciliation, settlement, or compromise between parties at variance compare arbitrator

More from Merriam-Webster on mediator

Nglish: Translation of mediator for Spanish Speakers

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