knockback vs recusancy

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. 

recusancy

noun
  • Obstinate refusal or opposition. 

  • The state of being a recusant; nonconformity. 

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