Noun
One who drives quickly or without subtlety, one who often engages in and/or is fond of slamming and flooring the accelerator often.
The leadfoot screeched to a stop inches from the tree.
A driver who does not compensate the throttle position of the vehicle for road conditions or terrain, invariably slowing down while going uphill and speeding up while going downhill.
Out of the way, leadfoot!