papa vs uncle-in-law

papa

noun
  • Dad, daddy, father; a familiar or old-fashioned term of address to one’s father. 

  • A parish priest in the Greek Orthodox Church. 

  • A pet name for one's grandfather. 

uncle-in-law

noun
  • The husband of one's uncle or aunt (parent's sibling). 

  • The uncle of one's wife. 

  • The uncle of one's husband. 

How often have the words papa and uncle-in-law occurred in a corpus of books? (source: Google Ngram Viewer )