chopper vs pocketknife

chopper

noun
  • A knife for chopping food, especially one with a large oblong blade. 

  • A tool for chopping wood; an axe/ax. 

  • A thick mitten, usually with yellow leather on the outside. 

  • The penis. 

  • A helicopter. 

  • An assault rifle, especially a fully-automatic one (e.g. an AK-47). 

  • A type of road motorcycle, especially as used by biker/bikie gangs. 

  • A crude tool with an irregular cutting edge formed by removing flakes from one side of a stone. 

  • A high-bouncing batted ball. 

  • The bluefish (Pomatomus saltatrix). 

  • Any of various electronic switches used to interrupt one signal under the control of another. 

verb
  • To travel or transport by helicopter. 

pocketknife

noun
  • A knife with blades or tools that the user can fold or retract into its handle, and of a size small enough for carrying safely and handily in a pocket, especially when suited to heavier duty uses or ad hoc applications outdoors or in workshops. 

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