cringle n.  a circular brass eye let into a sail for attaching a line for outhaul, reefing, etc. 

Dacron n. tradename of a synthetic fiber used for making strong, stretch-resistant rope or sailcloth. 

diesel engine n. (after Rudolph Diesel, a German inventor). An internal combustion engine in which ignition is achieved by the heat of compression. 

diesel vent n. on the Menger Cat, an engine compartment ventilator set in the cockpit coaming. 

dock master n.  the person in charge of a dock(s). 

downhaul  n. a line used to pull down the luff or forward edge of a sail. 

draft n. 1 .  depth of a boat below the waterline. 2. the particular shape of a sail that enables a sailboat to go to the windward. 

dropboard n. the board that closes off the entrance to the cabin. 

eyebolt n. a bolt with an eye on the end, used on the mast for attaching the halyard blocks, also on the stem for attachment to a trailer. 

fairlead n.  a guide through which a line passes. 

fiberglass  n. a fabric made from fine strands of glass, also , a very strong composite of fiberglass and resin, widely used in boatbuilding. 

Fiberglas n.  tradename for a brand of fiberglass. 

figure eight knot n. a stopper knot tied in the end of a line. 

flag halyard n. a light line used to hoist a flag. 

foot n. the lower edge of a sail. 

forestay n. a wire rope from the mast to the tang on the stem or bowsprit. 

gaff n. the spar supporting the head of a sail. 

gaff saddle n. a curved plate at the bottom of the gaff, bearing against the mast, allowing hoisting and rotation of the gaff. 

gelcoat n.  a smooth opaque outer layer acting as finish and protection on fiberglass. 

genoa or  genoa jib n. a large headsail used on sloops and other non-catboats. 

gooseneck n. the universal joint on the forward end of the boom. 

gudgeon n. the female half of a rudder pivot. see pintle. 

gunter rig n. an essentially triangular sail with a high peaked gaff almost parallel to the mast. 

gybe  see jybe. 

halyard n. a line used to hoist a sail. A gaff-rigged sail requires two halyards: a throat halyard and a peak halyard. 

head n. 1. the top of a sail. 2. a ship's toilet. This term has many other uses with the general meaning of front  or  top . 

heel n . a boat leaning over at some angle. 

isophthalic  adj. a particular formulation of gelcoat. 

jib n . headsail. 

jib sheet n . jib sail shape and trim control line. 

jiffy reefing n . jiffy reefing, also called slab reefing or single line reefing, is quicker and easier than conventional reefing or conventional roller reefing and involves folding the sail in sections, or slabs, along the boom. One or two reefing lines placed through the reef cringles at the sail's luff and leach edges are used to pull those points down tight to the boom, creating a new tack and clew for the sail. Reefing lines can be led back to the cockpit, and crew members can perform reefing without going on deck in heavy weather. In jiffy reefing there is no need to tie to the boom at the reef cringles on the sail. The equipment for jiffy reefing is often integrated with Dutchman flaking, a furling technology that flakes (or folds up) the sail on alternate sides of the boom rather than on a messy pile on one side of the boom. 

