hunting knife vs skean

hunting knife

noun
  • A large knife designed for use in hunting animals, usually with a smooth front edge and a back edge that is partially serrated for sawing. 

skean

noun
  • A double-edged, leaf-shaped, typically bronze dagger formerly used in Ireland and Scotland. 

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