extinction

Definitions

General English

  • noun the act of putting out a fire

General Science

Astronomy

  • In biology, the annihilation of an entire species. In astronomy, the dimming and reddening of starlight by interstellar dust, which in free space in our part of the galaxy seems to happen at a rate of about one magnitude per 1000 parsecs, away from major dust clouds. The dimming of starlight by the Earth’s atmosphere before it reaches ground-based telescopes is also termed extinction.

Medical

  • noun the destruction or stopping of something
  • noun the lessening or stopping of a conditioned behavioural response through lack of reinforcement
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