novel vs opus

novel

noun
  • A fable; a short tale, especially one of many making up a larger work. 

  • A new legal constitution in ancient Rome. 

  • A work of prose fiction, longer than a novella. 

adj
  • Original, especially in an interesting way; new and striking; not of the typical or ordinary type. 

  • Newly made, formed or evolved; having no precedent; of recent origin; new. 

opus

noun
  • A work, especially of art. 

  • A work of music or set of works with a specified rank in an ordering of a composer's complete published works. 

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