Aroadster (alsospider,spyder) is an open two-seat car with emphasis on sporting appearance or character.[1][2] Initially an American term for a two-seat car with no weather protection, its usage has spread internationally and has evolved to include two-seatconvertibles.
The roadster was also a style of racing car driven inUnited States Auto Club (USAC) Championship Racing, including theIndianapolis 500, in the 1950s and 1960s. This type of racing car was superseded byrear-mid-engine cars.

The term "roadster" originates in the United States, where it was used in the 19th century to describe a horse suitable for travelling.[3][4] By the end of the century, the definition had expanded to includebicycles and tricycles.[5] In 1916, the United StatesSociety of Automobile Engineers defined a roadster as: "an open car seating two or three. It may have additional seats onrunning boards or in rear deck."[6] Since it has a single row of seats, the main seat for the driver and passenger was usually further back in the chassis than it would have been in atouring car.[4][7]: 258 Roadsters usually had a hoodeddashboard.[7]: 257
In the United Kingdom, historically, the preferred terms were "open two-seater" and "two-seat tourer".[8][9] Since the 1950s, the term "roadster" has also been increasingly used in the United Kingdom. It is noted that the optional 4-seat variant of theMorgan Roadster would not be technically considered a roadster.[citation needed]
The term "spider" or "spyder," sometimes used in names for convertible models, is said to come from before the automobile era. Some 19th-century lightweight horse-drawnphaetons had a small body and large wooden wheels with thin spokes; they were nicknamed "spiders" because of their appearance; the nickname was transferred to sports cars, although they did not look similar.[10]
In 1962,Chevrolet introduced theMonza Spyder, a turbocharged version of itsCorvair compact, available as a convertible or coupe. Although not a true 2 passenger vehicle, it featured upgraded suspension and other equipment to classify it as a "sporty car."
Auto racing began with the first earnest contests in1894 in Europe, and in1895 in the United States. Some of the earliest race cars were purpose-built or stripped for the greatest speed, with minimal or no bodywork at all, leading to a body style aptly named 'speedster'. The cut-down speedster body-style really took form in the 1900s. After removing most of the body (and fenders), an empty platform on the ladder-frame chassis was mounted with one or two seats, a gas tank, and spare tyres.[11]
American manufacturers Mercer and Stutz started offering ready-made racing speedsters, intentionally built to be driven to race(-track), raced, and driven back by their owner – essentially the firsttrack day cars.[11]
The immediate predecessor to the roadster was therunabout, a body style with a single row of seats and no doors, windshield, or other weather protection. Another predecessor was thetouring car, similar in body style to the modern roadster except for its multiple rows of seats. By the 1920s roadsters were appointed similarly to touring cars, with doors, windshields, simple folding tops, and side curtains.[4]
Roadster bodies were offered on automobiles of all sizes and classes, from mass-produced cars like theFord Model T and theAustin 7 to extremely expensive cars like theCadillac V-16, theDuesenberg Model J andBugatti Royale.
By the 1970s "roadster" could be applied to any two-seater car of sporting appearance or character.[12] In response to market demand they were manufactured as well-equipped as convertibles[13] with side windows that retracted into the doors. Popular models through the 1960s and 1970s were theAlfa Romeo Spider,MGB andTriumph TR4.
The highest selling roadster is theMazda MX-5, which was introduced in 1989.[14][15][16] The early style of roadster with minimal weather protection is still in production by several low-volume manufacturers and fabricators, including the windowlessMorgan Roadster, the doorlessCaterham 7 and the bodylessAriel Atom.

The termroadster was used to describe a style of racing cars competing in theAAA/USAC Championship Cars series (the IndyCar equivalents of the time) from 1952 to 1969. The roadster engine and drive shaft are offset from the centerline of the car. This allows the driver to sit lower in the chassis and facilitates a weight offset which is beneficial on oval tracks.[17]
One story of why this type of racing car is referred to as a "roadster" is that a team was preparing a new car for the Indianapolis 500. They had it covered in a corner of their shop. If they were asked about their car they would try and obscure its importance by saying that it was just their (hot rod) "roadster". After the Indianapolis racer was made public, the "roadster" name was still attached to it.[citation needed]
Frank Kurtis built the first roadster to race and entered it in the1952 Indianapolis 500. It was driven byBill Vukovich who led for most of the race until a steering failure eliminated him. The Howard Keck owned team with Vukovich driving went on to win the 1953 and 1954 contests with the same car.Bob Sweikert won the1955 500 in a Kurtis after Vukovich was killed while leading.A. J. Watson,[18] George Salih and Quinn Epperly were other notable roadster constructors. Watson-built roadsters won in1956,1959 –1964 though the1961 and1963 winners were actually close copies built from Watson designs. The1957 and1958 winner was the same car built by Salih with help by Epperly built with a unique placement of the engine in a 'lay down' mounting so the cylinders were nearly horizontal instead of vertical as traditional design dictated.[19] This gave a slightly lowercenter of mass and a lower profile.
Roadsters continued to race until the late 1960s, although they became increasingly uncompetitive against the new rear-engined racing cars. The last roadster to complete the full race distance was in1965, whenGordon Johncock finished fifth in the Wienberger Homes Watson car. The last roadster to make the race was built and driven byJim Hurtubise in the1968 race and dropped out early.[20]
Some pavement midget roadsters were built and raced into the early 1970s but never were dominant.[21]
roadsternoun an open car without rear seats.
Roadster. A two-passenger open car of sporting appearance.
Here it is, with other body types and distinctions, officially determined recently by the Nomenclature Division of the Society of Automobile Engineers:
(for the purposes of this British publication) 'In order to avoid confusion, however, the universally understood terms "Tourer", "Coupé", "Saloon", "Limousine", etc., have been adopted, adding the American term 'Roadster' as the two-seater edition of the tourer.'