pervert vs understand

pervert

verb
  • to misinterpret designedly. 

  • To turn another way; to divert. 

  • To corrupt; to cause to be untrue; corrupted or otherwise impure 

  • To misapply, misuse, use for a nefarious purpose 

  • To become perverted; to take the wrong course. 

noun
  • A person whose sexual habits are not considered acceptable. 

understand

verb
  • To believe, to think one grasps sufficiently despite potentially incomplete knowledge. 

  • To stand underneath, to support. 

  • To grasp a concept fully in one's mind, especially (of words, statements, art, etc.) to be aware of the meaning of and (of people) to be aware of the intent of. 

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