Protraction and Retraction
Proctaction means the state of being protracted; especially : protrusion of the jaws
The word protraction may be used to describe a movement so it could be used in an expression such as “protraction of the shoulder is one of the movements used in rowing”.
The only joints capable of protraction are the shoulder joint and the jaw.
The movement of retraction is the opposite of the movement of protraction.
The word retraction may be used to describe a movement so it could be used in a sentence such as: “Retraction of the shoulders is part of some routines in gymnastics, acrobatics and dance.”