castoff vs unoriginal

castoff

noun
  • Something that has been rejected or discarded; a reject. 

adj
  • discarded, rejected. 

unoriginal

noun
  • A person or work that does not exhibit originality. 

adj
  • Not being the first or earliest version of something, not original. 

  • Lacking originality. 

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