What is the meaning of extinction?

noun

• No longer active; extinguished.
  • usage: "the extinction of the volcano"
• No longer in existence.
  • usage: "the extinction of a species"
  • synonyms: defunctness
• The reduction of the intensity of radiation as a consequence of absorption and radiation.
• Complete annihilation.
  • usage: "they think a meteor cause the extinction of the dinosaurs"
  • synonyms: extermination
• A conditioning process in which the reinforcer is removed and a conditioned response becomes independent of the conditioned stimulus.
  • synonyms: experimental extinction
• The act of extinguishing; causing to stop burning.
  • usage: "the extinction of the lights"
  • synonyms: extinguishing, quenching