roach coach
n.— «Mary Nelson’s vehicle is an example of what the city calls a mobile catering business, or what is described in the food code as an “itinerant restaurant.” In the slang of the trade, trucks like this are called roach coaches and are found wherever there is a market for fast food delivered fast, such as a construction site or an office with no nearby restaurant.» —“Building a High-Rise” by Carl Nolte San Francisco Chronicle (California) Nov. 5, 2006. (source: Double-Tongued Dictionary)