goodbye vs nod

goodbye

noun
  • An utterance of goodbye, the wishing of farewell to someone. 

verb
  • To say goodbye; to wish somebody farewell on parting. 

intj
  • Farewell; a formula used to another person or persons when the speaker, writer, or person addressed is departing. 

nod

noun
  • An instance of inclining the head up and down, as to indicate agreement, or as a cursory greeting. 

  • A nomination. 

  • Approval. 

  • A reference or allusion to something. 

verb
  • To signify by a nod. 

  • To incline the head up and down, as to indicate agreement. 

  • To allude to something. 

  • To sway, move up and down. 

  • To make a mistake by being temporarily inattentive or tired 

  • To briefly incline the head downwards as a cursory greeting. 

  • To fall asleep while under the influence of opiates. 

  • To gradually fall asleep. 

  • To head; to strike the ball with one's head. 

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