| 1. | a red lamp, used as a traffic signal to mean “stop.” |
| 2. | an order or directive to halt an action, project, etc.: There's a red light on all unnecessary expenses. |
| 3. | a children's running game in which players must stop when “Red light!” is called. |
| 4. | a signal of danger; warning. |
[red-lahyt] 
| Informal. to stop or deter by means of or as if with a red light. |