Headlight n. : A light, with a powerful reflector, placed at the head of a locomotive, or in front of it, to throw light on the track at night, or in going through a dark tunnel.

Example:
How do I choose Headlight bulbs for my car?

Taxonomy
headlamps, low beam, lamps, vehicles, reflector, filament, bulb, high beam, lens, headlamp bulbs, traffic, driver, optics, light sources, burner, car, beams, halogen.

Defination from the web:
headlight beam control. 5.1 Headlamp levelling control. 5.2 Directional headlamps. 5.3 Advanced front-lighting system ... Night driving is difficult and dangerous due to the blinding glare of headlights from oncoming traffic. ... Main article: Automatic headlight dimmer ...