traffic light

American  

noun

traffic lights plural

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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Other Word Forms

Noun Inflected Forms

• traffic lights
  plural

Etymology

Origin of traffic light

First recorded in 1925–30

Example Sentences

Seven months ago, a self-driving Waymo made an illegal U-turn at a traffic light right in front of police officers in San Bruno.

From Los Angeles Times • May 1, 2026

"A broad traffic light assessment of the public finances would make governments' multiple objectives – and the associated trade-offs faced – much more transparent and explicit," she said.

From BBC • Feb. 18, 2026

Some call them a "traffic light system"; critics have likened them to Nando's spice cards.

From BBC • Nov. 11, 2025

Indian home minister Amit Shah said the blast occurred around 7 p.m. in a Hyundai i20 car at a traffic light near the Red Fort.

From The Wall Street Journal • Nov. 10, 2025

Lexie slowed as they approached a traffic light and Pearl noticed dark rings beneath her eyes.

From "Little Fires Everywhere" by Celeste Ng

Related Words

• red light
• stoplight
• traffic control
• yellow light