re·ac·tor noun \rē-ˈak-tər\
: one that reacts: as a : a chemical reagent b : an individual reacting to a stimulus c : an individual reacting positively to a foreign substance (as in a test for disease) <reactors to tuberculin>
a : a piece of equipment in which a chemical reaction and especially an industrial chemical reaction is carried out b : a device for the controlled release of nuclear energy (as for producing heat)
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