I fairly recently learned the term
digitigrade, to describe the anatomy of a creature that stands on its toes rather than on the flat of its foot, like cats and birds.
I'm trying to narrow that down a little more now. Some animals like a cat or dog (or us), the toes are fairly static as they walk. Contrast that to the toes of a bird where on the upstep the toes... pull together, for lack of a better description, and spread apart as they step down on the foot, as shown in this video.
What is the proper term used to describe that motion and style of walking, or that type of functional foot, where the toes pull together and then spread apart as the foot goes up and down?