What is a defining feature of a semitrailer?

A semitrailer is uniquely characterized by the fact that it is designed to rest upon or be towed by another vehicle, typically a tractor unit. This arrangement allows the semitrailer to connect with the towing vehicle through a fifth wheel coupling, providing support while allowing for greater maneuverability compared to a full trailer.

This design is essential for the operation of commercial transport, facilitating the movement of heavy loads while maintaining a level of stability. Unlike a full trailer, which has its own wheels at the front and can operate independently, a semitrailer relies on the towing vehicle for support and stability. This relationship enables the efficient transport of freight, making it a vital component of the trucking industry.

In summary, the defining feature of a semitrailer is its reliance on another vehicle for towing, which is integral to its purpose and functionality in cargo transport.