Os secundum metatarsi

The metatarsal bones, or metatarsus are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes.

Lacking individual names, the metatarsal bones are numbered from the medial side (the side of the great toe): the first, second, third, fourth, and fifth metatarsal (often depicted with Roman numerals).

The metatarsals are analogous to the metacarpal bones of the hand.

The lengths of the metatarsal bones in humans are, in descending order: second, third, fourth, fifth and first.