rē+ noun
( -s )
Etymology: International Scientific Vocabulary react + -or
1. : one that reacts: as
a. : a chemical reagent
b.
(1) : the subject reacting to a stimulus in a psychological experiment
(2) : the subject reacting positively to a foreign substance (as in a test for disease)
tuberculous cattle are reactors to tuberculin
2. : an organism that produces reaction in its environment
3. : a coil, winding, or conductor of small resistance and large inductance used in an alternating-current circuit to impede or throttle the current or to change its phase
4.
a. : a piece of equipment in which a chemical reaction is carried out especially on an industrial scale
batch and continuous reactors
b. : an apparatus in which a chain reaction of fissionable material is initiated and controlled (as for generation of heat for power or for production of plutonium from uranium) — called also atomic furnace, atomic pile, nuclear reactor, pile