893: The Acceptability of Yid May 19, 2017
So long as someone is proficient enough in a given language, even without needing to read any grammar-books that speaker would have an understanding of how to form new words from existing patterns. 'Yiddish' is an adjective, and nominally is the name of a language; like many others that have those same qualities such as 'Swedish', 'Finnish', and 'Danish', to form the demonym, one simply has to remove the suffix, '-ish'. Neverhtless, while 'Swede', 'Finn', and 'Dane' are all fine to use—common enough and not offensive—'Yid', created by back-formation, is considered informal and often offensive, though it should be noted that 'Jew' is perfectly accetable. By the same pattern, someone who is Amish could be thought of as an Am, but this is not used by any or at least many people seriously.