enervation vs sickliness

enervation

noun
  • State of being enervated; debility. 

  • Act of enervating; debilitation. 

sickliness

noun
  • The state or characteristic of weakness, incapacity, or physical distress due to poor health, especially of a chronic nature. 

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