jerigonza

jargon; gibberish; a language game like Pig Latin or backslang; a game in which the letter p is inserted after every syllable (or sometimes distinguished as jeringozo, if every vowel)

“No entendían los cabreros aquella jerigonza de escuderos y de caballeros andantes, y no hacían otra cosa que comer y callar, y mirar a sus huéspedes, que, con mucho donaire y gana, embaulaban tasajo como el puño.” — The goatherds did not understand this jargon about squires and knights-errant, and all they did was to eat in silence and stare at their guests, who with great elegance and appetite were stowing away pieces as big as one's fist.

From Occitan gergons, from Old Occitan gergon, from Old French jargon.