Clark,I believe that a term used in shipping by shipping managers. Here is some other terms he uses. Rail Trailer:This is a trailer or container. Hy/Rail: Trailer that well be taken to the intermodule yard then place on a train.This tells us this trailer must be loaded and picked up and delivered by a preset cutoff time for loading onto rail cars.Note freight bills will be place inside of the trailer(s). A Poky truck line: A trucking firm that is slow on pickup of loaded trailers and or deliveries. Slow freight to China..A freight car or rail trailer that is over due.A over due truck Hot Load: A expedited freight shipment. No show..Truck that does not show up on time.