callus vs knife

callus

noun
  • The new formation over the end of a cutting, before it puts out rootlets. 

  • A shining area on the frons of many species of Tabanomorpha (horse flies and relatives). 

  • The material of repair in fractures of bone; a substance exuded at the site of fracture, which is at first soft or cartilaginous in consistency, but is ultimately converted into true bone and unites the fragments into a single piece. 

  • A hardened area of the skin (especially on the foot or hand) caused by repeated friction, wear or use. 

verb
  • To form such hardened tissue. 

knife

noun
  • Any blade-like part in a tool or a machine designed for cutting, such as that of a chipper. 

  • A weapon designed with the aforementioned specifications intended for slashing and/or stabbing and too short to be called a sword. A dagger. 

  • A utensil or a tool designed for cutting, consisting of a flat piece of hard material, usually steel or other metal (the blade), usually sharpened on one edge, attached to a handle. The blade may be pointed for piercing. 

verb
  • To betray, especially in the context of a political slate. 

  • To positively ignore, especially in order to denigrate; compare cut. 

  • To cut with a knife. 

  • To use a knife to injure or kill by stabbing, slashing, or otherwise using the sharp edge of the knife as a weapon. 

  • To cut through as if with a knife. 

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