inappropriate vs unappropriate

inappropriate

adj
  • Not appropriate; not suitable for the situation, time, or place. 

  • Improper; adult; sexual. 

unappropriate

adj
  • Inappropriate; unsuitable. 

verb
  • To take from private possession; to restore to the possession or right of all. 

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