On a square rigged ship, the spanker is a gaff rigged fore-and-aft sail set from and aft of the aftmost mast. Almost all square rigs with more than one mast have one or two spankers, which evolved from the driver sail. Some also carry a topsail above the uppermost or only spanker, called the gaff sail.
On a racing or cruising yacht, a spanker is an additional headsail set beside and to windward of a spinnaker when running downwind. It is often of bright colours to match the particular spinnaker with which it is designed to be used, is relatively narrow and is sometimes called a tallboy. The spanker has largely fallen from favour except among photographers.
Sail burton (Naut.), a purchase for hoisting sails aloft for bending.
Sail yard (Naut.), the yard or spar on which a sail is extended.
To strike sail (Naut.), to lower the sails suddenly, as in saluting, or in sudden gusts of wind; hence, to acknowledge inferiority; to abate pretension.
Modern sails are designed such that the warp and the weft of the sailcloth are oriented parallel to the luff and foot of the sail.
In modern times a sail is cut of the extreme size which is capable of being carried in fine weather, and when the wind increases in strength it is reefed -- part is gathered up and fastened by reef points, small cords attached to the sail.
Outboard of the square sails might be set studdingsails [studding sail, studsail, stun's'l) -- a sail on a special spar, extended outboard of a square sail or sails, for added sail area in moderate winds.