approximate vs counterfactual

approximate

adj
  • Nearing correctness; nearly exact; not perfectly accurate. 

  • Approaching; proximate; nearly resembling. 

verb
  • To come near to; to approach. 

  • To carry or advance near; to cause to approach. 

  • To estimate. 

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. 

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