From a line: Ends step forward and quarter out as centers quarter out and step forward. Finishes as couples back to back. From a wave: All Step Thru and Quarter Out. Original centers take one step forward. Finishes as couples back to back.
NOTE: Dancers generally have enough difficulty with plain Explodes without our imposing a Reverse variation on them.
This definition is from The Handbook of Modern Square Dancing by Jay King.
It is provided here for informational and educational purposes only.