fetter vs retard

fetter

verb
  • To restrain or impede; to hamper. 

  • To shackle or bind up with fetters. 

noun
  • A chain or similar object used to bind a person or animal – often by its legs (usually in plural). 

  • Anything that restricts or restrains. 

retard

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

  • To put off; to postpone. 

  • To decelerate; to slow down. 

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 fetter and retard occurred in a corpus of books? (source: Google Ngram Viewer )