The man in charge of the brake-apparatus of a railway train.
The man who has the general charge and control of a stage coach or a railway train.
The guard at the rear of a railway train.
A guard on a railway train.
The brakeman or guard on a train.
In Russia or (historical) the Soviet Union: (a) a guide; (b) a conductor or guard on a train.
U.S. slang. A railroad brakeman. Now rare.