exemplar vs illustration

exemplar

noun
  • A copy of a book or piece of writing. 

  • A handwritten manuscript used by a scribe to make a handwritten copy; the original copy of what gets multiply reproduced in a copy machine. 

  • A role model. 

  • A well known usage of a scientific theory. 

  • Something fit to be imitated; an ideal, a model. 

  • A pattern after which others should be made; an archetype. 

  • Something typical or representative of a class; an example that typifies. 

illustration

noun
  • A picture designed to decorate a publication, or elucidate a literary work. 

  • A calculated prevision of insurance premiums and returns (life insurance) 

  • The state of being illustrated, or of being made clear and distinct. 

  • The act of illustrating; the act of making clear and distinct; 

  • Something which illustrates; a comparison or example intended to make clear or apprehensible, or to remove obscurity. 

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