a person, animal, or organism that reacts to a stimulus, esp. under test or experimental conditions; spec. one showing an immune response to a specific antigen, the subject reacting positively to a foreign substance(as in a test for disease): tuberculous cattle are reactors to tuberculin

device or vessel within which chemical processes are carried out for experimental or manufacturing purposes, keemiaaparaat, milles teostatakse mingit keemilist reaktsiooni. Mõningaid tööstuses kasutatavaid reaktoreid nimetatakse ka kolonnideks, autoklaavideks jms.

a device containing fissionable material in sufficient quantity and so arranged as to be capable of maintaining controlled, self-sustaining nuclear fission chain reaction, seade, milles teostatakse aatomituumade lõhustumise juhitavat ahelreaktsiooni. Lõhustuvate ainetena (tuumkütus) kasut. uraani ja plutooniumi isotoope. T. toodab soojust, neutron-, gamma- ja neutriinokiirgust ning lõhustumiskildudena keskm. aatommassiga elementide radioaktiivseid isotoope.