balmoral vs field boot

balmoral

noun
  • A heavy walking shoe. 

  • A Scottish cap with a flat top and a plume but no brim; a blue bonnet. 

  • A figured woollen petticoat. 

  • An Oxford shoe. 

field boot

noun
  • a type of walking boot 

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