used to vs usta

used to

adj

  • Accustomed to, tolerant or accepting of. 

verb

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

usta

abbrev

  • use to 

  • used to: accustomed to 

  • used to: formerly did 

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