instep vs kicks

instep

noun
  • A section of any footwear covering that part of the foot. 

  • In horses, the hind leg from the ham to the pastern joint. 

  • The arched part of the top of the foot between the toes and the ankle. 

kicks

noun
  • Shoes. 

  • Pleasures, thrills. 

  • Commissary, or the balance of a commissary account. 

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