extinction vs matricide

extinction

noun
  • The action of making or becoming extinct; annihilation. 

  • The absorption or scattering of electromagnetic radiation emitted by astronomical objects by intervening dust and gas before it reaches the observer. 

  • The inability to perceive multiple stimuli simultaneously. 

  • The fading of a conditioned response over time if it is not reinforced. 

matricide

noun
  • The killing of one's mother. 

  • A person who kills his or her mother. 

How often have the words extinction and matricide occurred in a corpus of books? (source: Google Ngram Viewer )