Word forms: (regular plural) backup lights
noun (Automotive engineering: Vehicle components, Lighting and electrical/electronic systems) A backup light is a lamp used to provide light behind a vehicle, particularly when reversing.
SIMILAR WORDS: backup lamp ⇒ The color of the light from a backup light shall be white, in accordance with regulations. ⇒ Backup lights must not be continuously lit when the vehicle is in forward motion. ⇒ When the driver shifts the transmission into reverse, the contacts of the backup light switch are closed.
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