boar vs razorback

boar

noun

  • A male pig. 

  • A male bear. 

  • A male boar (sense 1). 

  • A wild boar (Sus scrofa), the wild ancestor of the domesticated pig. 

  • A male guinea pig. 

razorback

noun

  • A feral pig. 

  • The rorqual or finback whale. 

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