A Secondman or Second man is a railway employee who assists the driver of a train with his duties. For this reason the term driver's assistant is also used.

Secondman
Secondman
SECOND MAN
Praise Assecondman Held for Policemurders
Second man charged with
Second man suspected of ordering abduction of Lipetsk lawmaker detained in Anapa
3 TOTS FIGHT FOR LIFE AFTER CANOE CAPSIZES IN SEA LOCH; Man, 35, and Girl Aged 10 Swim to Shore but Second Man, 34, Missing
Madagascar - Second Mangoro Forestry Project
Second Man Gets Life Sentence in Norwin Grad's Killing
The Analysis of a Heritage Campus Using the Principle of the Second Man
Second man charged in shooting death
ATTACKS IN LONDON: Oval Tube Suspect Is Second Man Arrested
40-Second Man