a medical condition in which the arch on the inside of the foot is lower or flatter than usual, so that the entire bottom of the foot touches the ground, or a foot that shows this condition;
e.g. These shoes can correct flatfoot if they are worn regularly.
(noun)
(informal, dated) an officer of the police force, especially one who patrols a regular area;
e.g. They saw the local flatfoot approaching and rushed to hide their things.