Yiddish translation almost always involves more than just Yiddish…
Yiddish was orignally formed from a mixture of other languages: German, Hebrew, Slavic languages, etc. In contemporary Yiddish-speaking communities, the languages continues to morph and borrow words from the languages of the host countries where it is spoken. For example, American Yiddish is rich in English words, while Israeli Yiddish may be up to 25% Modern Hebrew. As a result, when a chassid from Jerusalem meets a chassid from New York, they will sometimes have a hard time understanding each other.
But even in pre-war Europe, Yiddish always had widely varying dialects and pronunciations, and speakers borrowed heavily from their host language. This presents a challenge for a Yiddish translator, who is generally best-versed in a particular dialect, for example, American Yiddish or Polish Yiddish. However, a “Yiddish translator” will often be called upon to translate lots of word in Russian, Hungarian or German. That’s why our translators work as a team; each of our translators knows a particular dialect of Yiddish and they help each other out.
On more than one occasion, I’ve gotten an email from someone asking me to translate a Yiddish document, but when I open it up, it’s not Yiddish at all! In such a case, it’s usually Hebrew – many people cannot tell the difference. Once a document was in Aramaic, and another I received one in German. We have no problem doing translations in any of these languages. We also regularly translate Russian and Polish documents, which come up a lot for people researching Jewish genealogy. As far as I’m concerned, Hebrew, Aramaic, German, Russian, Polish and any other language, all go come the territory for a Yiddish translation service. They are all common “Jewish” languages, and after all, Yiddish just means “Jewish.”