balmoral vs moon boot

balmoral

noun
  • An Oxford shoe. 

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

  • A heavy walking shoe. 

  • A figured woollen petticoat. 

moon boot

noun
  • A type of footwear made popular in the 1970s, with a thin rubber outsole and no distinct left or right feet. 

  • A large hard plastic covering, used to protect a broken foot or ankle while it heals. 

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