disastrous vs grievous

disastrous

adj
  • Of the nature of a disaster; calamitous. 

  • Foreboding disaster; ill-omened. 

grievous

adj
  • Serious, grave, dire, or dangerous. 

  • Causing grief, pain, or sorrow. 

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