rear spoiler

A spoiler is an automotive aerodynamic device whose intended design function is to 'spoil' unfavorable air movement across the body of a vehicle in motion, usually manifested as lift, turbulence, or drag. Spoilers on the front of a vehicle are often called air dams and are positioned below the front of the vehicle.
Spoilers are frequently fitted to race and high-performance sports cars, although they have also become common on passenger vehicles. Spoilers are added to cars primarily for styling and either have little aerodynamic benefit or worsen the aerodynamics.
The term "spoiler" is often mistakenly used interchangeably with "wing". An automotive wing is designed to generate downforce as air passes around it, not simply to disrupt existing airflow patterns. Rather than decreasing drag, automotive wings actually increase drag.

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