indigestible vs sleepy

indigestible

adj
  • Difficult to accept; unpalatable. 

  • Difficult or impossible to digest. 

noun
  • Anything that is difficult to digest. 

sleepy

adj
  • Suggesting tiredness. 

  • Quiet; without bustle or activity. 

  • Tending to induce sleep. 

  • Tired; feeling the need for sleep. 

  • Dull; lazy. 

noun
  • The gum that builds up in the eye; sleep, gound. 

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