activator noun7 •One who, or that which, activates. •Something that activates a catalyst •Any chemical or agent which regulates one or more genes by increasing the rate of transcription. •A type of effector that increases the rate of enzyme-mediated reactions. •A type of dopant used in phosphors and scintillators. •An agent that enables the flotation of a mineral or minerals. •A hand-held device that delivers a controlled fast thrust to a joint, muscle, etc., to help stimulate nervous system activity. formsactivators