sleepy vs soporific

sleepy

adj
  • Tending to induce sleep. 

  • Quiet; without bustle or activity. 

  • Tired; feeling the need for sleep. 

  • Suggesting tiredness. 

  • Dull; lazy. 

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

soporific

adj
  • Tending to induce sleep. 

  • Boring, dull. 

noun
  • Something boring or dull. 

  • Something inducing sleep, especially a drug. 

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