marble
Auto racing term for a ball of rubber on the track that has come off of a tire. Usually used in the plural. Multiple marbles take over entire racing lanes on the outside of normal racing grooves or lanes. Marbles decrease grip, causing cars to crash in corners. Drivers compare driving on marbles to driving on ice.
Example:
Dale Earnhardt, Jr., has been making great time on the high side. But that was too high. He got up into the marbles and slapped the wall.
Dale Earnhardt, Jr., has been making great time on the high side. But that was too high. He got up into the marbles and slapped the wall.