Mediator

Mediator may refer to:
 * A person who engages in mediation
 * Business mediator, a mediator in business
 * Vanishing mediator, a philosophical concept
 * Mediator variable, in statistics

Chemistry and biology

 * Mediator (coactivator), a multiprotein complex that functions as a transcriptional coactivator
 * Endogenous mediator, proteins that enhance and activate the functions of other proteins
 * Gaseous mediator, chemicals produced by some cells that have biological signalling functions
 * Mediator, a brand name of benfluorex, a withdrawn appetite suppressant medication

Internet, software, and computer

 * Mediator pattern, in computer science
 * A mail server's role in email forwarding

Other

 * Mediator, guitar pick or plectrum, an accessory for picking strings of musical instruments
 * The Mediator, a teen book series by Meg Cabot (some under the pseudonym Jenny Carroll)
 * The Mediator, a television documentary produced by Open Media
 * Mediator (Christ as Mediator), an office of Jesus Christ
 * Linesman/Mediator, a radar system in the United Kingdom
 * HMS Mediator, three ships of the British navy
 * USS Mediator, a ship of the United States navy
 * Mediator, brand name for benfluorex, an anorectic and hypolipidemic agent
 * "Mediator", a song by Jinjer from Wallflowers (album)