retard vs seclude

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. 

seclude

verb
  • To shut or keep out; exclude; preclude. 

  • To shut off or keep apart, as from company, society, etc.; withdraw (oneself) from society or into solitude. 

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