From a wave, two-faced line or diamond formation: Centers arm turn 3/4 as the ends do a U-turn back. Wave finishes as a diamond. Two faced line finishes as a facing diamond. Regular diamond finishes as a wave. Facing diamond finishes as a two faced line.
Bill Davis 1972
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.