distal phalanx, any one of the small distal bones in the third row of phalanges of the hand or the foot (second phalanx in the thumb and great toe). Each one at the end of the finger has a convex dorsal surface and a flat palmar surface, with a rough elevation at the end of the palmar surface that supports a fingernail and its sensitive pulp. The distal phalanx of each of the toes is smaller and more flattened than that of a finger; it also has a rough elevation to support the toenail and its pulp. Also called ungual phalanx.
