Couples Hinge Across: From parallel two-faced lines: Couples Hinge, Center Couples Trade, then Couples Hinge once more. Finishes in parallel two faced lines.
Single Hinge Across: From a box formation: Single Hinge, then Centers Trade and Single Hinge again. Finishes in another box formation.
John Cronin 1976
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.