illustration vs representation

illustration

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

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

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

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

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

representation

noun
  • The act of representing. 

  • An object that describes an abstract group in terms of linear transformations of vector spaces; (more formally) a homomorphism from a group on a vector space to the general linear group (group of all bijective linear transformations) on the space. 

  • A statement; a presentation of opinion or position, or an utterance made to influence the opinions or actions of others 

  • The lawyers and staff who argue on behalf of another in court. 

  • A figure, image or idea that substitutes reality. 

  • That which represents something else. 

  • The ability to elect a representative to speak on one's behalf in government; the role of this representative in government. 

  • A theatrical performance. 

  • An act of representing, i.e. presenting again. 

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