Anu says today's word means: The original or earliest version of a text, such as a musical composition or literary work. I thought, "Hey, maybe it's because of that Ur place". (I know the etymology is from the German, but for all I know it makes no difference.) But then at the end he says (italics mine), Interestingly, Ur was also the name of an ancient Sumerian city in Mesopotamia (now Iraq). So does that mean there's no connection?
Also--I'd never heard the term cell-yell before. It's kind of cute.