rescind vs undo

rescind

verb
  • To cut away or off. 

  • To repeal, annul, or declare void; to take (something such as a rule or contract) out of effect. 

undo

verb
  • To unfasten. 

  • To reverse the effects of an action. 

  • To impoverish or ruin, as in reputation; to cause the downfall of. 

noun
  • An operation that reverses a previous action. 

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