fastback

/ˈfæstˌbæk/
noun
  1. A car with a roof that slopes down smoothly to the rear, forming a continuous curve from the top to the back bumper.
    • Many collectors prefer fastbacks over sedans for their sleek styling.
    • He restored a classic 1960s fastback Mustang.
    • The fastback design gives the car a sporty, aerodynamic look.