guidon vs pennon

guidon

noun
  • A small pennant or banner carried by infantry soldiers to direct troop movement. 

  • A soldier assigned to carry such a banner. 

pennon

noun
  • A long pointed streamer or flag on a vessel. 

  • A thin, often triangular flag or streamer, especially as hung from the end of a lance or spear. 

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