From two dancers facing: Join both hands and circle as designated one quarter, one half, three quarters or full around. If no turning direction is given and the preceding movement has not established a circling direction, then the circling is to the left. Otherwise it will be in the direction indicated or in the direction already established by the preceding call.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.