"in a pearl white Cabriolet"

A 1950s convertible Jaguar
GNU Free Documentation LicenseA 1950s convertible Jaguar - Credit: Sfoskett
Cabriolet is one of the terms used to denote a soft-top or convertible car: a vehicle which has a detachable or fold-away roof, giving it the option of being a normal closed-roof or open-air car.

A cabriolet was originally, in the eighteenth century, a horse-drawn carriage with a large folding hood to cover its pair of occupants. As the vehicle was light and required only one horse it became the fashionable choice of transport in large Western cities and was used to convey passengers for a fare. It was soon shortened into ‘cab’, which is still used today to refer to a taxi.