début vs visibility

début

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

verb
  • To make one's début. 

visibility

noun
  • The degree to which things may be seen. 

  • The condition of being visible. 

  • The scope within which a variable or function is able to be accessed directly. 

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