enervate vs overstrain

enervate

verb
  • To weaken morally or mentally. 

  • To partially or completely remove a nerve. 

  • To reduce strength or energy; debilitate. 

adj
  • Made feeble; weakened. 

overstrain

verb
  • To subject to an excessive demand on strength, resources, abilities, or the imagination. 

noun
  • excessive strain 

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