retard vs retrench

retard

verb
  • To decelerate; to slow down. 

  • To put off; to postpone. 

  • 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. 

retrench

verb
  • To cut down or reduce. 

  • To furnish with a retrenchment (a defensive work within a fortification). 

  • To dig or redig a trench where one already exists. 

  • To terminate the employment of a worker to reduce the size of a workforce; to make redundant. 

  • To abridge; to curtail. 

  • To live less expensively; to economize. 

  • To confine; to limit; to restrict. 

  • To take up a new defensive position. 

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