disastrous vs internecine

disastrous

adj
  • Of the nature of a disaster; calamitous. 

  • Foreboding disaster; ill-omened. 

internecine

adj
  • Mutually destructive; most often applied to warfare. 

  • Characterized by struggle within a group, usually applied to an ethnic or familial relationship. 

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