lingo vs lingua franca

lingo

noun
  • Language, especially language peculiar to a particular group, field, or region; jargon or a dialect. 

lingua franca

noun
  • A common language used by people of diverse backgrounds to communicate with one another, often a basic form of speech with simplified grammar, particularly, one not the first language of any of its speakers. 

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