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

Israel said the attacks were responses to ceasefire violations, but mediators said the strikes threaten the fragile truce. —Wafaa Shurafa, Los Angeles Times, 31 Jan. 2026

Minnesota Attorney General Keith Ellison’s office, which regulates charities, became involved in discussions and assisted with finding mediators. —Frederick Melo, Twin Cities, 30 Jan. 2026

But the Republican president’s ambitions have expanded to envisioning the board as a mediator of worldwide conflicts, a not very subtle attempt to eclipse the Security Council, which is charged with ensuring international peace and security. —Edith M. Lederer, Chicago Tribune, 30 Jan. 2026

By advancing to phase two, the United States and mediator partners Egypt and Qatar must confront the more contentious issue of Hamas disarmament, which the group has long rejected. —Nidal Al-Mughrabi, USA Today, 29 Jan. 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