echoic vs unoriginal

echoic

adj
  • Imitative of a sound; onomatopoeic. 

  • Of or pertaining to an echo 

unoriginal

adj
  • Lacking originality. 

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

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

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