avouch vs début

avouch

verb
  • To declare freely and openly; to assert. 

  • To confirm or verify, to affirm the validity of. 

  • To acknowledge deliberately; to admit; to confess; to sanction. 

  • To appeal to; to cite or claim as authority. 

début

verb
  • To make one's début. 

noun
  • A person’s or thing’s first appearance before society or another audience; one’s “maiden voyage”. 

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