Foot drop, also known as dropped foot or drop foot, is the inability to raise the front part of the foot due to weakness or paralysis of the muscles that lift the foot (National Institute of Neurological Disorders).
Consequentially, people who have foot drop scuff their toes along the ground; they may also bend their knees to lift their foot higher than usual to avoid the scuffing, which causes what is called a "steppage" gait.