Medical Dictionary
mediator
noun me·di·a·tor \ˈmēd-ē-ˌāt-ər\
Medical Definition of MEDIATOR
: 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>
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