genticide vs internecion

genticide

noun
  • The killing of a race or nation of people; the slaughter of an ethnic group; a genocide. 

  • The killing of a kinsman or kinswoman; the murder of a blood relative. 

internecion

noun
  • destruction, massacre 

  • Mutual destruction. 

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