English Reference
noun

mediator

n.
US /ˈmidiˌeɪtɝ/ UK /mˈiːdɪˌeɪtɐ/ me·di·a·tor UK spelling mediators

  1. 01 C1 Advanced Formal Law

    someone who talks to two people or groups who are arguing to help them find a solution.

    a person who acts as a neutral intermediary between parties in a dispute to facilitate a settlement or agreement.

    Simple

    The company hired a mediator to help the manager and the staff resolve their argument.

    In context

    The government appointed a professional mediator to oversee the discussions between the union and the airline, hoping to prevent a nationwide strike.

  2. 02 C2 Proficiency Technical Science

    a substance in the body that carries information to a cell.

    a chemical substance, such as a hormone or neurotransmitter, that transmits information to a targeted cell.

    Simple

    Scientists are studying how this chemical mediator tells the brain to feel pain.

    In context

    The research focused on the role of inflammatory mediators in the body's immune response to chronic infection.

    Usage

    Often used in the phrase 'chemical mediator' or 'inflammatory mediator'.

Although an April ceasefire brokered alongside initial mediator Pakistan temporarily halted major combat, peace framework talks collapsed in June.

Al Jazeera· 15 Aug 2026

Hamas in a statement later called on mediators and the US-created Board of Peace overseeing the ceasefire to “compel” Israel to approve the road map for next steps.

The Guardian· 16 Aug 2026

From Middle English mediatour, mediatoure, mediatur, medyatour, from Middle French mediateur, mediatur or its etymon Latin mediātor (“one who mediates”), from mediātum, supine of mediō (“be in the middle”), from medius (“middle”). By surface analysis, mediate + -or.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin mediātor
Level C1 · Advanced
Frequency Frequent
Updated