Sheets. Ropes or chains which extend the lower corners of square sails in the operation of sheeting home.
Shifting suits (of sails). The operation of removing a ship's sails, and replacing them with others.
Shrouds. Wire ropes of great strength, which support lateral strains on masts.
Shroud-screws. Iron contrivances by which shrouds are hove taut.
Sidelights. A sailing ship carries two of these between sunset and sunrise: one green, to starboard; one red, to port.
Sights. Observations to help in the finding of a ship's position.
Skid. A wooden contrivance on which ship's boats rest.
Skysails. The uppermost square sails; the fifth, sixth, or seventh sails from the deck according to the mast's rig.
Slatting. The noise made by sails flogging in the wind.
Slush. Grease, melted fat.