dingus vs knob-end

dingus

noun
  • A fool or incompetent person. 

  • A gadget, device, or object whose name is either unknown, forgotten, or omitted for the purpose of humor. 

  • penis 

knob-end

noun
  • A stupid or contemptible person 

  • Used other than figuratively or idiomatically: see knob, end. The end of something that is shaped into a knob. 

  • The glans penis 

How often have the words dingus and knob-end occurred in a corpus of books? (source: Google Ngram Viewer )