When is "groucho" not a comedian? A "seagull" not a bird? A "banana" not a fruit, and a "taco cart" not a food stand? What's the "Castle rock rule" and when should you call for a "buff & puff"? And why expect trouble when the A.D. (assistant director) knowingly mumbles "Gone With the Wind in the morning, Dukes of Hazzard after lunch"? An oral tradition gathered and passed down for more than a hundred years, the language of moviemaking, like other secret lexicons, is the only accepted way of communicating on a set--and is all but unknown to the outside world. Technical, odd,...