Baragouin

She spoke the rude French of the fishing villages, where the language lives chiefly as a baragouin, mingled often with words and forms belonging to many other tongues.

Source: wiktionary

Now in almost every island the negro idiom is different. So often have some of the Antilles changed owners, moreover, that in them the negro has never been able to form a true patois. He had scarcely acquired some idea of the language of his first masters, when other rulers and another tongue were thrust upon him, and this may have occurred four or five times. The result is a baragouin that defies analysis, a totally incoherent agglomeration of speech forms, a bewildering medley, fantastic, astonishing, incomprehensible, almost weird.

Source: wiktionary

[Jean-Jacques] Rousseau remained contemptuously aloof and described the language of [John] Milton as a terrible baragouin, too rude for his polite ears to decipher.

Source: wiktionary

In technical parlance, [Lewis] Carroll's coined language is neither laternois, the compulsive repetition of obsessional sounds which have nothing to do with a real tongue, and which one hears, for instance, is glossolalia, nor baragouin, the imitation of the sounds of another language, but charabia, the imitation of one's own language.

Source: wiktionary