Fastback

A fastback is a car body style whose roofline slopes continuously down at the back. It is a form of back for an automobile body consisting of a single convex curve from the top to the rear bumper. This automotive design element "relates to an interest in streamlining and aerodynamics, and has gone in and out of fashion at various times."

The fastback word can also designate the car itself. The style is seen on two-door as well as four-door body designs as distinguished by their "level of commonality in vehicle construction as defined by number of doors and roof treatment (e.g., sedan, convertible, fastback, hatchback)." "Some automakers have persisted in describing a model by a word different from common usage" and thus seeming inconsistencies have persisted, such as "certain fastbacks are, technically, two-door sedans or pillared coupes."

Automobile designers in the 1930s began using elements of aircraft aerodynamics to smooth out the boxy-looking vehicles of their day. Some designs that were ahead of their time when exhibited during the early 1930s included "teardrop" streamlining of the car's rear; a configuration similar to what would become known as 'fastback' 25 years later." 'Fastback' was first recognized as a definition by Merriam-Webster in 1954, many years before the term 'hatchback' was popularized and entered the dictionary in 1970. Opinions vary as to whether the terms are mutually exclusive.

A contributor to an automotive-interest website singles out the unusual Stout Scarab from the early 1930s as "Possibly the epitome of the early fastback definition". The Packard 1106 Twelve Aero Sport Coupe, introduced in 1933, is also cited as a fastback that foreshadowed trends which continued into the 1940s.

Starting in 1935, Australian automakers introduced fastback body design that became known as the "sloper". It was first designed by General Motors' Holden as one of the available bodies on Oldsmobile, Chevrolet, and Pontiac chassis. The sloper design was added by Richards Body Builders in Australia to Dodge and Plymouth models in 1937, by Ford Australia in 1939 and 1940, as well as a sloper style made on Nash chassis. According to automotive historian G.N. Georgano, "the Slopers were advanced cars for their day."

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Wikipedia