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[ak-tuh-vey-ter] /ˈæk təˌveɪ tər/
a person or thing that activates.
Chemistry, Biochemistry. a catalyst.
any impurity in a mineral that causes luminescence.
Compare inhibitor (def 3).
Orthodontics. a removable appliance, usually of hard plastic, that is worn in the mouth instead of a fixed appliance to help align the teeth and improve the relationship of the lower jaw to the upper.
Origin of activator
Related forms
nonactivator, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the Web for activator
Historical Examples
  • The Black Doctor closed his eyes wearily and flipped an activator switch.

    Contamination Crew Alan Edward Nourse
  • They may have been, and the use of the activator may have been extorted from one of them.

    Temple Trouble Henry Beam Piper
  • Finally, he poked the activator bar, and watched as the machine spat out tape.

    The Players Everett B. Cole
  • Nargyll wants to move your ship into one of the sheds, but the activator key's gone.

activator in Medicine

activator ac·ti·va·tor (āk'tə-vā'tər)

  1. An agent that renders another substance active or accelerates a process or reaction.

  2. The fragment produced by chemical cleavage of a proactivator that induces the enzymatic activity of another substance.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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