inadequate vs unappropriate

inadequate

adj
  • Not adequate; not fit for the purpose 

noun
  • An individual who is inadequate. 

unappropriate

adj
  • Inappropriate; unsuitable. 

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

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