accustom vs naturalize

accustom

verb
  • To make familiar by use; to cause to accept; to habituate, familiarize, or inure. 

naturalize

verb
  • To make natural 

  • To make (a word) a natural part of the language, using the native homologue of each phoneme (and often for each morpheme) of the imported word (e.g., native inflections). 

  • To study nature. 

  • To limit explanations of a phenomenon to naturalistic ones and exclude supernatural ones. 

  • To grant citizenship to someone not born a citizen. 

  • To acclimatize an animal or plant. 

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