disallow vs undergo

disallow

verb
  • To reject as invalid, untrue, or improper 

  • to overrule a colonial legislation by the sovereign-in-privy council 

  • To refuse to allow 

undergo

verb
  • To suffer or endure; bear with. 

  • To experience; to pass through a phase. 

  • The project is undergoing great changes. 

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