**Aft:** toward or near the stern.
**Beam:** width of a hull.
**Bilge:** curved section between the bottom and the side of the hull.
**Bilge Keel:** a longitudinal fin fitted to the outside of a boat at the turn of the bilge.
**Block Coefficient:** a hull form coefficient that is the ratio of underwater volume of a boat to the volume of a
rectangular block, the dimensions of which are the effective length, draft, and beam.
**Bow:** the forward end of a boat.
**Bulkhead:** vertical wall which divides the boat.
**Centerline:** the middle vertical plane of a boat, extending from the bow to the stern.
**Chine:** the angle running the length of a boat where two planks meet.
**Coaming:** vertical plating bounding a hatch for the purpose of stiffening the edges of the opening.
**Deck:** platform in a boat that corresponds to a floor in a house.
**Depth: **vertical distance from waterline to the bottom of the boat’s hull.
**Displacement:** equal to the weight of water displaced by the boat at its greatest allowable draft.
**Draft:** the depth of the boat below the waterline measured vertically to the lowest part of the hull.
**Forward:** toward or near the bow.
**Freeboard:** the vertical distance from the lowest point on the gunwale to the waterline.
**Gunwale:** structural supports along the sheer of a boat.
**Hard-chine:** a hull style with two chines and a keel.
**Hull:** the structural body of a ship, including shell, framing, decks, bulkheads, etc.
**Keel:** the principal fore-and-aft component of a ship’s framing, located along the centerline of the bottom hull.
**Length Over All (LOA):** the extreme length of a boat measured from the foremost point of the forward stem
to the aftermost part of the stern.
**Maximum Section Coefficient**: a hull form coefficient that is the ratio of the maximum cross section area to
the area formed by a rectangle, the dimensions of which are the maximum beam and depth.
**Port Side:** the left hand side of the boat when looking forward.
**Rocker:** the curvature along the boat’s centerline.
**Sheer:** the longitudinal curve of a boat’s top edge of the hull.
**Stability:** the tendency of a ship to remain upright or the ability to return to her normal upright position when
listed by the action of waves, wind, etc.
**Starboard Side: **the right hand side of the boat when looking forward.
**Stem (bow):** the bow frame forming the apex of the intersection of the forward sides of a boat.
**Stern:** the aft end of a boat.
**Tumblehome:** when the sheer line beam is narrower than the maximum beam.
**Waterline:** plane where the water touches the hull at a given loading.
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