1. a light sail set above the skysail on a square-rigged ship
Usage: nautical; historical

Examples

• The crew hoisted the moonsail to catch every breath of wind.
• In favorable conditions, the ship’s moonsail helped maximize speed.
• The moonsail was the highest sail on the tall ship’s mainmast.
• Only experienced sailors were trusted to handle the delicate moonsail.
• The captain ordered the moonsail taken down as the wind picked up.