nanny vs sheepdog

nanny

noun
  • A female goat. 

  • A child's nurse. 

  • A godmother. 

  • A grandmother. 

verb
  • To treat like a nanny's charges; to coddle. 

  • To serve as a nanny. 

sheepdog

noun
  • A breed of dog used for guarding sheep. 

  • A breed of dog, used for herding sheep. 

  • A police officer. 

verb
  • To chaperon or shepherd. 

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