roll bar

or rollbar

noun

1. a heavy steel transverse bar in the form of an inverted U rising from the framework of an automobile to prevent its occupants from being crushed if the vehicle rolls over.

Word History and Origins

Origin of roll bar¹

First recorded in 1950–55

Example Sentences

“Springs and shocks and roll bars and all that stuff,” he adds, “are stiffer than a regular car, to be able to maximize and take advantage of the performance of the tires and how low and wide the car is.”

From Popular-Science