heraldic device vs heraldry

heraldic device

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. 

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