What is the meaning of Mediator?

One who negotiates between parties seeking mutual agreement.

A chemical substance transmitting information to a targeted cell.

mediator

mediator, intermediary, go-between

mediator (one who negotiates between parties seeking mutual agreement)

mediator (person who professionally listens to the conflicting parties and tries to reach a settlement, which sometimes helps avoid a court case)

mediator (chemical substance transmitting information to a targeted cell)

mediator, intermediary

Source: wiktionary.org