The operator of a railway locomotive WordNet 3.0 & Open English WordNet

A train driver, engine driver, engineman or locomotive driver, commonly known as an engineer or railroad engineer in the United States and Canada, and also as a locomotive handler, locomotive engineer, locomotive operator, train operator, or motorman, is a person who operates a train, railcar, or other rail transport vehicle. Wikipedia

An operator of a locomotive Wikipedia Disambiguation

The person who drives the engine of a train. Wiktionary

Person. Wiktionary (translation)

A person who controls motion of substance (such as a locomotive). Wiktionary