There were several of his priests and lawyers present (as I conjectured by their habits), who were commanded to address themselves to me; and I spoke to them in as many languages as I had the least smattering of, which were High and Low Dutch, Latin, French, Spanish, Italian, and Lingua Franca, but all to no purpose.
There are no more uses of "lingua franca" in the book.
Show samples from other sources
Except that English is its chief lingua franca and Newspeak its official language, it is not centralized in any way.
George Orwell -- 1984
She forbade boys like Grace and Bien from speaking to each other in Swahili and required them instead to speak English—the team’s lingua franca.