hypnotic vs sleeping tablet

hypnotic

noun

  • A soporific substance. 

  • A person who is, or can be, hypnotized. 

adj

  • Of, or relating to hypnosis or hypnotism. 

  • Inducing sleep; soporific. 

sleeping tablet

noun

  • A sleeping pill. 

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