counterfactual vs unofficial

counterfactual

adj
  • Contrary to known or agreed facts; untrue. 

  • Of or in comparison to a hypothetical state of the world. 

noun
  • A conditional statement in which the conditional clause is false. 

  • A claim, hypothesis, or other belief that is contrary to the facts. 

  • A hypothetical state of the world, used to assess the impact of an action. 

unofficial

adj
  • Implicitly true but withheld and/or contradicted by authority. 

  • Not officially established. 

  • Not acting with official authority. 

  • Not listed in a national pharmacopeia etc. 

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