The term 'Truck Stop Sight' refers to the vehicles that are commonly seen at truck stops. The three solutions for this term are RIG (3 letters), SEMI (4 letters), and TRACTORTRAILER (14 letters). RIG stands for a large truck with multiple axles, usually used for hauling heavy loads. A SEMI is a tractor-trailer combination, which is a large truck with a trailer attached to it. Finally, a TRACTORTRAILER is a large truck with a trailer attached to it, but with a tractor unit instead of a cab. All of these vehicles are commonly seen at truck stops, hence the term 'Truck Stop Sight'.