The set of red, yellow and green lights at a road junction that tells drivers when to stop and go. This is mainly American English — in America, stoplight and traffic light are both completely normal, with stoplight sounding a bit more casual and more common in everyday speech and in giving directions ('turn left at the second stoplight'). British speakers say traffic lights almost always, and would find stoplight noticeably American. The word can also mean the red brake light on the back of a car, though most people now say brake light for that. Note that Americans measure distance by them: 'it's three stoplights down' means three junctions away, not three lamps. Written as one word; stop light as two is also seen but less common.

紅綠燈（美式說法；台灣一般就講紅綠燈，英式為 traffic light）