‘雾灯’ (wù dēng) literally means ‘fog light’ — a specialized automotive headlight designed to improve visibility in low-visibility conditions such as fog, heavy rain, snow, or dust storms. The first character 雾 (wù) means ‘fog’ or ‘mist’, and the second character 灯 (dēng) means ‘lamp’ or ‘light’. Together, they form a compound noun referring specifically to the front or rear lights on vehicles that emit a wide, low beam of yellow or white light to reduce glare and scatter.

These lights are commonly installed on cars, trucks, and buses, and are regulated by traffic safety standards in China and elsewhere. Drivers are expected to use fog lights only when visibility drops below about 100–200 meters; using them unnecessarily can dazzle other drivers and is illegal in many areas. Fog lights are distinct from regular headlights, high beams, or daytime running lights — both in function and placement on the vehicle.