instep

/IH0 N S T EH0 P/
noun
  1. 1

    The arched part of the top of the foot between the toes and the ankle.

  2. 2

    A section of any footwear covering that part of the foot.

  3. 3

    In horses, the hind leg from the ham to the pastern joint.

Source: https://en.wiktionary.org/wiki/instep