a High German language with an admixture of vocabulary from hebrew and the Slavic languages, written in Hebrew letters, and spoken mainly by Jews in eastern and central Europe and by Jewish emigrants from these regions and their descendants.
a language spoken as a vernacular by Jews in Europe and elsewhere by Jewish emigrants, usually written in the Hebrew alphabet. Historically, it is a dialect of High German with an admixture of words of Hebrew, Romance, and Slavonic origin, developed in central and E Europe during the Middle Ages
1875, from Yiddish yidish, from M.H.G. jüdisch "Jewish" (in phrase jüdisch deutsch "Jewish-German"), from jude "Jew," from O.H.G. judo, from L. Judaeus (see Jew). The Eng. word has been re-borrowed in Ger. as jiddisch.