lethetic vs unconscionable

lethetic

adj
  • Failing to mirror reality, purely escapist or nonsensical. 

unconscionable

adj
  • Not conscionable; unscrupulous and lacking principles or conscience. 

  • Excessive, imprudent or unreasonable. 

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