Doc Martens vs overshoe

Doc Martens

noun
  • Dr. Martens-brand footwear, especially a style of high lace-up leather boot with air-cushioned sole, traditionally associated with British skinheads, adopted by other subcultures at various times. 

overshoe

noun
  • To prevent damage to a floor. 

  • To protect from water or mud. 

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