repudiate vs validate

repudiate

verb
  • To reject the truth or validity of; to deny. 

  • To be repudiated. 

  • To refuse to have anything to do with; to disown. 

  • To refuse to pay or honor (a debt). 

validate

verb
  • To check or prove the validity of; verify. 

  • To have its validity successfully proven. 

  • To render valid. 

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