mediator

noun

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

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.
McHale nails the role of mediator and doesn’t sacrifice any dignity in the process. Matt Donnelly, Variety, 31 Mar. 2026 Islamabad has emerged as a mediator, having relatively good ties with Washington and Tehran, after what Pakistani officials call weeks of quiet diplomacy. ABC News, 29 Mar. 2026 Pakistan has emerged as a mediator, having relatively good ties with both Washington and Tehran. Dallas Morning News, 29 Mar. 2026 Pakistan has emerged as a key mediator and is scheduled to host a meeting attended by the foreign ministers of several regional powers on Sunday. Rhea Mogul, CNN Money, 28 Mar. 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

Browse Nearby Words

Cite this Entry

“Mediator.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mediator. Accessed 3 Apr. 2026.

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

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