pacemaker vs twitter

pacemaker

noun
  • A set of nerves which stimulate the heart to beat. 

  • One who sets the pace in a race, to guide the others. 

  • A medical implement that is used to stimulate a heart to beat by simulating the action of the natural pacemaker. 

twitter

noun
  • A slight trembling of the nerves. 

  • The sound of a succession of chirps as uttered by birds. 

  • A tremulous broken sound. 

  • Unwanted flicker that occurs in interlaced displays when the image contains vertical detail that approaches the horizontal resolution of the video format. 

verb
  • To make the sound of a half-suppressed laugh; to titter; to giggle. 

  • To have a slight trembling of the nerves; to be excited or agitated. 

  • To utter a succession of chirps. 

  • (of a person) To talk in an excited or nervous manner. 

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