One may be mounted close to a grille

• Bad weather auto accessory
• Bright light in inclement conditions
• Front-of-car accessory
• Low-visibility auto accessory
• Light used in murky conditions
• Auto-front accessory
• Headlight that provides strong beam for use in foggy weather
• Aid for dealing with pea soup

Wiktionary Word definitions in Wiktionary
n. A wide automotive lamp intended to increase visibility in poor weather conditions.