Examples from the Web for skysail
Single iron cross-trees at the head of long topgallant-masts, to support royal and skysail masts.The Sailor's Word-Book|William Henry Smyth
In these, the topgallant, royal and skysail masts are all one stick.
And Skysail Jack and I peered and knew each other under the wreckage.The Jacket (The Star-Rover)|Jack London
When the royal is taken in, haul the skysail yard down with the royal yard, and furl the sail in with the royal.
I shared my Java and grub with him, learned about Skysail Jack, and then learned about him.The Road|Jack London