busby vs shako

busby

noun
  • A fur hat, usually with a plume in the front, worn by certain members of the military or brass bands. 

shako

noun
  • A stiff, cylindrical military dress hat with a metal plate in front, a short visor, and a plume. 

  • A bearskin or busby. 

  • The squilla or mantis shrimp. 

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