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Medical Dictionary


noun ac·ti·va·tor \ˈak-tə-ˌvāt-ər\

Medical Definition of activator

  1. 1:  a substance (as a chloride ion) that increases the activity of an enzyme—compare coenzyme

  2. 2:  a substance given off by developing tissue that stimulates differentiation of adjacent tissue; also :  a structure giving off such a stimulant

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