disallowance vs knockback

disallowance

noun
  • The action of not allowing, or of withdrawing allowance. 

  • A power a higher level authority has to disallow particular legislation of the lower level jurisdiction; such as a federal government disallowing state/provincial legislation, or the crown disallowing federal legislation. 

knockback

noun
  • A rejection; a refusal. 

  • A blow that causes the recipient to fall or move backwards, a knock back; a recoil. 

  • Something that impedes or reverses progress; a setback. 

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