heraldry vs lieutenant junior grade

heraldry

noun
  • An armorial ensign along with its history and description. 

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

  • Pageantry. 

lieutenant junior grade

noun
  • A commissioned officer of the United States Navy whose rank is above an ensign's and below a lieutenant, or a corresponding rank in other navies. 

  • A commissioned officer in the United States Coast Guard, Public Health Service, or National Atmospheric and Oceanic Administration whose rank is above an ensign and below a lieutenant. 

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