[ noun ] any sail set forward of the foremast of a vessel <noun.artifact>
Headsail \Head"sail`\ (-s[=a]l`), n. (Naut.) Any sail set forward of the foremast. --Totten.
The modest sail plan is split into three via the cutter rig, giving greater flexibility and safety since crews on deck are always handling smaller sails than would be the case with a single headsail.
Her sails were in shreds, except for one small headsail, the only one she could use.