Gennaker

The gennaker is rigged like a spinnaker but the tack is fastened to the hull or to a bowsprit.

This is optimal for generating lift at larger angles of attack.

[1] The gennaker is a specialty sail primarily used on racing boats to bridge the performance gap between a genoa and a spinnaker.

It is sometimes the only downwind sail on board because it is easier to use and less expensive than a spinnaker.

Due to its geometry, the sail is less prone to collapsing than a spinnaker.