semáforo
/seˈmafoɾo/ · B2 · noun · m
traffic light
🚦 Greek sema (sign) + phoros (bearer) = sign-bearer, a device that carries signals
Semáforo comes from Greek sêma, meaning sign or signal, plus -phoros, meaning bearing or carrying. So it is literally a signal-bearer. Flag semaphore and the traffic light both carry signals to others.