horrendous vs monstrous

horrendous

adj
  • Extremely bad; awful; terrible. 

monstrous

adj
  • Hideous or frightful. 

  • Enormously large. 

  • Of, or relating to a mythical monster; full of monsters. 

  • Freakish or grotesque. 

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