From two facing couples with hands joined as though to circle: Without releasing hands, the couple designated will dive under an arch made by the other couple. Having finished the dive thru, the active couple will separate and move out to form the ends of a line (reverse facing direction). The arching couple will turn under their own arms without letting go to become centers of the new line.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.
