headlight

Short definition from Wiktionary

Noun

1. 1
   A bright light, with a lens and reflector, on the front of a motor vehicle (or originally a ship or train), designed to illuminate the road when driving at night; normally one of a pair.
2. 2
   A woman's breast.
3. 3
   A woman's erect nipples, partially masked by clothing.
4. 4
   A jewel; especially a diamond.
5. 5
   Lysergic acid diethylamide (LSD).