Definition: Roadster is a type of car designed to drive on roadways, similar to a convertible but not as open-skin or rigidly built like a convertible. They typically have a sports body shape and are known for their low center of gravity and nimble handling. Definition: A roadster is a type of car that is designed to be driven on roads rather than in traditional sports cars, often having a unique silhouette and appearance. It is usually made from carbon fiber or other lightweight materials and has a high performance engine and suspension systems to handle the conditions of road driving.