Throughout the world, wherever Jews have lived, they have spoken and/or written differently from the non-Jews around them. Their languages have differed by as little as a few embedded Hebrew words or by as much as a highly variant grammar. A good deal of research has been devoted to a number of Jewish languages, including Yiddish, Judeo-Spanish, Judeo-Arabic, Judeo-Italian, Jewish English, and Jewish Neo-Aramaic. This website displays information about several Jewish languages, as well as about some of the researchers who have written about them.
The list of languages for which they provide contacts, descriptions, and basic bibliographies includes Hebrew, Jewish Aramaic, Jewish English, Jewish Malayalam, Judeo-Arabic, Judeo-French, Judeo-Greek, Judeo-Iranian, Judeo-Italian, Judeo-Persian, Judeo-Portuguese, Judeo-Provençal, Judeo-Spanish/Judezmo/Ladino, and Yiddish; other languages for which they provide only Ethnologue links are Israeli Sign Language, Judeo-Alsatian, Judeo-Berber, Judeo-Crimean Tatar/Krimchak, Judeo-Georgian, Judeo-Slavic/Canaanic, Judeo-Tadjik/Bukharan, Judeo-Tat/Juhuric, and Karaim—a tantalizing list!
Here’s a bit from the Jewish Malayalam page:
One of the most notable features of Jewish Malayalam is the presence of fossilized elements from the pre-Malayalam layer. These archaisms exist at several levels, including lexicon, morphology, phonology, and semantics. A semantic example can be found in one of the wedding songs: the bride is described as covering her head with three types of flowers that have NaRRam. The word NaRRam exists in contemporary Tamil, Malayalam, and other local languages with the meaning ‘bad smell’. However, in this case the word is used with its old Tamil sense: ‘good smell’. This is just one example of the many elements of Jewish Malayalam that may seem like contemporary Tamil borrowings but are actually archaic remnants from before Malayalam split off from Tamil.