collage vs opus

collage

noun
  • The technique of producing a work of art of this kind. 

  • A picture made by sticking other pictures onto a surface. 

  • A composite object or collection (abstract or concrete) created by the assemblage of various media; especially for a work of art such as text, film, etc. 

verb
  • To make into a collage. 

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 collage and opus occurred in a corpus of books? (source: Google Ngram Viewer )