inefficacious vs unappropriate

inefficacious

adj
  • Not effective. 

  • Incapable of having the intended consequence. 

unappropriate

adj
  • Inappropriate; unsuitable. 

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

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