hasten vs retard

hasten

verb
  • To cause some scheduled event to happen earlier. 

  • To move or act in a quick fashion. 

  • To make someone speed up or make something happen quicker. 

retard

verb
  • To put off; to postpone. 

  • To decelerate; to slow down. 

  • To keep delaying; to continue to hinder; to prevent from progressing. 

noun
  • Retardation; delay. 

  • A slowing down of the tempo; a ritardando. 

  • A person or being who is extremely stupid or slow to learn. 

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