attrit vs water down

attrit

verb
  • To be reduced in quantity through attrition. 

  • To lose, or to kill, troops by attrition due to sustained firepower. 

  • To engage in attrition; to quit or drop out. 

  • To wear down through attrition, especially mechanical attrition. 

noun
  • One who voluntarily or involuntarily leaves a company; a termed employee. 

water down

verb
  • To make weaker, less effective. 

  • To simplify or oversimplify; to make easier; to make less difficult. 

  • To dilute; to add water to. 

  • To make less restrictive; to make more lenient. 

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