(of a sail) pointed at the top or head
(of a sailing vessel or rig) having sails that are triangular
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Examples from the Web for jib-headed
A jib-headed trysail was set on the mainsail to ease the steering gear.Yachting Vol. 1|Various.
A gaff-headed trysail is better than a jib-headed, but it is more bother to set.On Yachts and Yacht Handling|Thomas Fleming Day
The mainboom was lashed amidships, and a jib-headed storm trysail was sheeted aft.