heraldry vs icon

heraldry

noun
  • The profession or art of devising, granting and blazoning coats of arms, tracing genealogies and ruling on questions of protocol or rank. 

  • An armorial ensign along with its history and description. 

  • Pageantry. 

icon

noun
  • A person or thing that is the best example of a certain profession or some doing. 

  • A small picture that represents something. 

  • An image, symbol, picture, or other representation usually as an object of religious devotion. 

  • A type of religious painting portraying a saint or scene from Scripture, often done on wooden panels. 

  • A word, character, or sign whose form reflects and is determined by the referent; onomatopoeic words are necessarily all icons. 

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