repeal vs validation

repeal

verb
  • To recall; to summon (a person) again; to bring (a person) back from exile or banishment. 

  • To cancel, invalidate, annul. 

  • To suppress; to repel. 

noun
  • An act or instance of repealing. 

validation

noun
  • Something, such as a certificate, that validates something; attestation, authentication, confirmation, proof or verification. 

  • The process of identifying a new prisoner's gang affiliation. 

  • The process whereby others confirm the validity of one's emotions. 

  • The act of validating something. 

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