Definition of "green light" in English

Noun

1. 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.

2. Approval, or permission to proceed.

   • We have a green light on the project. Work starts today.

3. 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.