accelerator
ac·cel·er·a·tor
noun \ik-ˈsel-ə-ˌrāt-ər, ak-\Definition of ACCELERATOR
: one that accelerates: as a : a muscle or nerve that speeds the performance of an action <a cardiac accelerator> b : a substance that speeds a chemical reaction c : an apparatus for imparting high velocities to charged particles (as electrons)
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