motor equivalence
the ability to use different movements, produced by either the same or different parts of the body, to perform a task under different conditions. For example, the task of writing one’s name may be performed (a) on paper, with a pen held in the hand, by moving the fingers and wrist; (b) on a blackboard, with chalk held in the hand, by moving the arm; or (c) in the sand, using a toe, by moving the leg.