A vehicle designed to allow a handbrake or the train brake to be operated by a person other than the driver. Since, in the UK before the advent of continuous brakes, a guard (conductor) was provided to operate the brake on his vehicle to assist the driver stop the train, the "luggage van" was used and it became known as the brake van. On freight trains, the same term was used for the vehicle used by the guard. In the US it is called a "caboose".
Passenger train brake vans were often combined with a passenger coach to form a "brake coach" as in "brake third" denoting a vehicle with a third class passenger section and a guard's position.