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Noun: extinction  ik'stingk-shun or ek'stingk-shun
  1. No longer active; extinguished
    "the extinction of the volcano"
  2. No longer in existence
    "the extinction of a species";
    - defunctness
  3. (physics) reduction of the intensity of radiation as a consequence of absorption or scattering
  4. Complete annihilation
    "they think a meteor caused the extinction of the dinosaurs";
    - extermination
  5. A conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus
    - experimental extinction
  6. The act of extinguishing; causing to stop burning
    "the extinction of the lights";
    - quenching

Derived forms: extinctions

See also: extinct

Type of: action, activity, annihilation, conclusion, conditioning, death, disintegration, ending, inaction, inactiveness, inactivity, natural action, natural process, termination

Encyclopedia: Extinction