hellacious vs hellish

hellacious

adj
  • horrible, awful, hellish, agonizing 

  • nasty, repellent. 

  • Remarkable, unbelievable, unusual. 

hellish

adj
  • infernal, related or similar to hell 

  • causing great pain, discomfort or distress 

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