anesthetic vs somnific

anesthetic

adj
  • Insensate: unable to feel, or unconscious. 

  • Causing anesthesia; reducing pain sensitivity. 

noun
  • A substance administered to reduce the perception of pain or to induce numbness for surgery and may render the recipient unconscious. 

somnific

adj
  • Causing sleep; somniferous. 

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