mediator

noun

me·​di·​a·​tor ˈmē-dē-ˌā-tər 

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

• negotiator
• conciliator
• intermediary
• peacemaker
• broker
• ambassador
• intercessor
• liaison
• middleman
• buffer
• attorney

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

The country has prided itself in recent years as being a key regional mediator. —Melanie Goodfellow, Deadline, 10 Mar. 2026

So Athena acts as a mediator who puts an end to the fighting? —Nina Metz, Chicago Tribune, 9 Mar. 2026

In the first episode, the peacemaking mission between Josh and Seth, in rural Montana, completely falls apart, and the mediator—who explains that this is his first official mediation—mostly just stands there as the neighbors trade insults and issue threats. —Tyler Foggatt, New Yorker, 6 Mar. 2026

Federal and state mediators have been involved. —Paula Wethington, CBS News, 3 Mar. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for mediator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

Kids Definition

mediator

noun

me·​di·​a·​tor ˈmēd-ē-ˌāt-ər 

: one that mediates

mediatory

-ē-ə-ˌtōr-ē, 

-ˌtȯr-

adjective

Medical Definition

mediator

noun

me·​di·​a·​tor ˈmēd-ē-ˌāt-ər 

: 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 

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