Cabrio is a shortened form of the French word--cabriolet. A cabriolet was a type of lightweight two-wheeled carriage with a folding top. Due to its relative small size a cabriolet is pulled by one horse. Cabrio is also used in German and Dutch to identify a type of two-wheeled carriage.
Cabrio is used in the automobile industry as a model name. The Cabrio is a model of a soft-top two-door convertible manufactured by Volkswagen. The Volkswagen Cabrio is a type of cabriolet, hence the shortened name--Cabrio.
In the automobile industry a cabriolet is a general term for a soft-top, two-door convertible coupe. Due to the fact that cabriolets were often used as hacks (or carriages for hire), the word cabriolet was eventually shortened to the more common word known today--cab.