reactor
re.ac.tor \re--'ak-t*r\ n 1: one that reacts; specif : a subject reacting positively to a for eign substance 2: a device (as a coil, winding, or conductor of small resistance) used to introduce reactance into an alternating-current circuit 3a: a vat for an industrial chemical reaction 3b: an apparatus in which a chain reaction of fissionable material is initi ated and controlled