Instep

n. upper section of the human foot between the ankle and the toes

The foot is a biological structure found in many animals that is used for locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws or nails.
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Instep /in·step/ the dorsal part of the arch of the foot. in·step n. The arched middle part of the foot between toes and ankle. [more]Instep - Community and Resources

Noun
1. the arch of the foot
(hypernym) arch
(hyponym) sunken arch, fallen arch
(part-holonym) foot, human foot, pes
2. the part of a shoe or stocking that covers the instep
(hypernym) covering
(part-holonym) shoe

(n.)
The arched middle portion of the human foot next in front of the ankle joint.
  

(n.)
That part of the hind leg of the horse and allied animals, between the hock, or ham, and the pastern joint.