certification vs laissez-passer

certification

noun
  • The granting of a certificate. 

  • The act of certifying. 

  • A professional qualification that certifies a person's ability. 

laissez-passer

noun
  • A pass or permit; a document permitting the bearer to travel, sometimes issued as an emergency passport. 

How often have the words certification and laissez-passer occurred in a corpus of books? (source: Google Ngram Viewer )