enervate vs keep under

enervate

verb
  • To weaken morally or mentally. 

  • To partially or completely remove a nerve. 

  • To reduce strength or energy; debilitate. 

adj
  • Made feeble; weakened. 

keep under

verb
  • To hold in subjection; hence, to oppress. 

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