irresponsible vs unoriginal

irresponsible

noun
  • Someone who is not responsible. 

adj
  • Lacking a sense of responsibility; performed or acting as though without responsibility; negligent. 

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 irresponsible and unoriginal occurred in a corpus of books? (source: Google Ngram Viewer )