trial run vs verification

trial run

noun
  • An empirical test of the suitability or effectiveness of a method or thing by running it at least once. 

  • An empirical test of the suitability or capability of a person or actor by letting him perform at least once. 

verification

noun
  • The operation of testing the equation of a problem, to see whether it truly expresses the conditions of the problem. 

  • The state of being verified. 

  • Confirmation; authentication. 

  • A formal phrase used in concluding a plea, to denote confirmation by evidence. 

  • The act of verifying. 

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