green light

green light noun: a traffic light in its green state (indicating that vehicles may proceed).

Image: Wazouille, Public domain, via Wikimedia Commons

Noun

green light (plural green lights)

A traffic light in its green state (indicating that vehicles may proceed).
- The drive home was much faster than usual; somehow we managed to hit every green light.
(idiomatic) Approval, or permission to proceed.
- We have a green light on the project. Work starts today.
- And Crossrail's Class 345 Aventra fleet finally has the green light to carry passengers to Heathrow Airport, after the Office of Rail and Road granted approval for the European Train Control System (ETCS) Level 2 overlay system.2020 May 20, “Network News: Class 345s finally able to serve Heathrow Airport”, in Rail, page 15
Synonyms:

go
(slang) A go-ahead to commit a crime, specifically to carry out a hit on someone (i.e. to kill).
- Yo man, I heard someone had put a green light out on you, so watch your back.

More languagesFewer languages

plural	green lights

From the standard red-green color scheme used in traffic lights and railway signals.

What does green light mean?: Green light means a traffic light in its green state (indicating that vehicles may proceed).
What is green light in Tamil?: Green light in Tamil is பச்சைவிளக்கு (paccaiviḷakku). See Green light meaning in Tamil.
What part of speech is green light?: Green light is a noun.
What is the plural of green light?: The plural of green light is green lights.

Adapted from Wiktionary: green light (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated: 2026-09-02

Pronunciation audio from Wikimedia Commons, each file under its own free license: en-au-green light.ogg.

Cite this entry: “green light.” Word.ws, https://word.ws/green_light. Based on Wiktionary, CC BY-SA 4.0.