illustration

/ˌɪləˈstreɪʃən/
noun
  1. A picture or drawing in a book, magazine, or other text that helps explain or decorate the content.
    • The children's book had a beautiful illustration on every page.
    • She added a diagram as an illustration to make the science concept clearer.
    • The magazine article included an illustration of the new building design.
  2. An example or story used to explain or prove something.
    • This case is a perfect illustration of how quickly technology changes.
    • The teacher used a personal story as an illustration of the importance of honesty.
    • He gave a simple illustration to show how the math problem works.