knockback vs prohibition

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. 

prohibition

noun
  • An act of prohibiting, forbidding, disallowing, or proscribing something. 

  • A law prohibiting the manufacture or sale of alcohol. 

  • A period of time when specific socially disapproved consumables are considered controlled substances. 

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