impending vs indigestible

impending

adj
  • Approaching; drawing near; about to happen or expected to happen. 

noun
  • Something that impends or threatens; an expected event. 

indigestible

adj
  • Difficult to accept; unpalatable. 

  • Difficult or impossible to digest. 

noun
  • Anything that is difficult to digest. 

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