signaller
noun/ˈsɪɡnələ(r)/
/ˈsɪɡnələr/
(US English signaler)
(also signalman)
- a person whose job is operating signals on a railway
（铁路上的）信号员，信号工 - a person trained to give and receive signals in the army or navy
（军队的）信号兵，通信兵