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

NewYork-Presbyterian nurses at that point rejected a similar proposal advanced by mediators. —Philip Marcelo, Fortune, 20 Feb. 2026

But his vision for the board to be a mediator of worldwide conflicts has led to skepticism from major allies. —Arkansas Online, 19 Feb. 2026

NewYork-Presbyterian nurses reject mediator's proposal Last week, NewYork-Presbyterian nurses overwhelmingly voted down a proposal, meaning more than 4,200 nurses are still on strike. —Christina Fan, CBS News, 19 Feb. 2026

But the Republican president’s new vision for the board to be a mediator of worldwide conflicts has led to skepticism from major allies. —Farnoush Amiri, Chicago Tribune, 19 Feb. 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