knife vs razor blade

knife

noun
  • 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. 

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

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

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. 

razor blade

noun
  • A thin piece of steel with a sharp edge that can be fitted into a razor. 

  • A replaceable cartridge in which razor blades are set, fitted into a razor. 

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