traffic light

American  

noun

1. a set of electrically operated signal lights used to direct or control traffic at intersections.

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traffic light British  

noun

1. one of a set of coloured lights placed at crossroads, junctions, etc, to control the flow of traffic. A red light indicates that traffic must stop and a green light that it may go: usually an amber warning light is added between the red and the green

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Etymology

Origin of traffic light

First recorded in 1925–30

Example Sentences

The company said its cars treat nonfunctioning traffic lights as four-way stops, but the added caution worsened congestion, prompting the decision.

From Barron's

When Chicago introduced electric-scooter rentals in 2019, the convenience came with downsides: Some riders ran traffic lights, frightened pedestrians and abandoned their battery-powered rides in the middle of the sidewalk.

From The Wall Street Journal

The answer involves Aurora kinases, a group of proteins that operate like strict traffic lights.

From Science Daily

The car adjusted its speed, handled turns, navigated stop signs, made lane changes on the freeway and even responded to traffic lights.

From The Wall Street Journal

A previous dress rehearsal highlighted the need for a new traffic light at a specific location to alleviate gridlock when military convoys move across the country.

From The Wall Street Journal

Related Words

• red light
• stoplight
• traffic control
• yellow light