razorback vs tusker

razorback

noun
  • A feral pig. 

  • The rorqual or finback whale. 

tusker

noun
  • An animal, such as a bull elephant or a boar, with large tusks. 

  • A tool used in peat cutting, a type of spade similar to a cascrom. 

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