Trundling is the practice of rolling large rocks or boulders down hillsides. We were trundling through the countryside at night. Not only schoolboys, but even graduate students at Cambridge enjoyed trundling hoops after their lectures. He was eventually released just as the Ferrari was trundling down the pit lane. By the late 1990s, over 13,000 vehicles were trundling through the town daily. Trundling is discouraged for safety and environmental concerns as well as to preserve artifacts.