[ 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


non·ac·ti·va·tor, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for activator

  • They may have been, and the use of the activator may have been extorted from one of them.

    Temple Trouble|Henry Beam Piper
  • Nargyll wants to move your ship into one of the sheds, but the activator key's gone.

  • Finally, he poked the activator bar, and watched as the machine spat out tape.

    The Players|Everett B. Cole

Medical definitions for activator

[ ăktə-vā′tər ]


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