ataraxic vs hypnic

ataraxic

adj

  • Of or pertaining to ataraxia or ataraxy 

  • ataractic; tranquilizing 

noun

  • An ataractic or tranquilizing agent. 

hypnic

adj

  • That induces sleep. 

noun

  • Any sleep-inducing drug. 

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