I learned his word for that last car on trains eighty years ago, always the last car or long freight trains. They were typically painted red, and had a low turret with windows from which the brakemen could watch the whole train ahead of them, watching for smoke indicating a "hot box" meaning failure of lubrication of the bearings of one of the wheels, with overheating and danger of collapse of the end of the axle of the wheel, capable of causing derailment.
But a few months ago, I encountered "caboose" meaning a temporary structure on deck of ships containing the cooking ovens.