accustomed vs used to

accustomed

adj
  • Familiar with something through repeated experience; adapted to existing conditions. 

  • Familiar through use; usual; customary. 

used to

adj
  • Accustomed to, tolerant or accepting of. 

verb
  • Formerly and habitually or repeatedly, but possibly no longer, did. 

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