Boating Basics Glossary of
Terms
A
ABAFT - Toward the rear (stern) of the boat. Behind.
ABEAM - At right angles to the keel of the boat, but not on the boat.
ABOARD - On or within the boat.
ABOVE DECK - On the deck (not over it - see ALOFT)
ABREAST - Side by side; by the side of.
ADRIFT - Loose, not on moorings or towline.
AFT - Toward the stern of the boat.
AGROUND - Touching or fast to the bottom.
AHEAD - In a forward direction.
AIDS TO NAVIGATION - Artificial objects to supplement natural landmarks indicating
safe and unsafe waters.
ALEE - Away from the direction of the wind. Opposite of windward.
ALOFT - Above the deck of the boat.
AMIDSHIPS - In or toward the center of the boat.
ANCHORAGE - A place suitable for anchoring in relation to the wind, seas and
bottom.
ASTERN - In back of the boat, opposite of ahead.
ATHWARTSHIPS - At right angles to the centerline of the boat; rowboat seats are
generally athwart ships.
AWEIGH - The position of anchor as it is raised clear of the bottom.
B
BATTEN DOWN - Secure hatches and loose objects both within the hull and on
deck.
BEAM - The greatest width of the boat.
BEARING - The direction of an object expressed either as a true bearing as shown on
the chart, or as a bearing relative to the heading of the boat.
BELOW - Beneath the deck.
BIGHT - The part of the rope or line, between the end and the standing part, on which
a knot is formed. BILGE - The interior of the hull below the floor boards.
BITTER END - The last part of a rope or chain.The inboard end of the anchor
rode.
BOAT - A fairly indefinite term. A waterborne vehicle smaller than a ship. One
definition is a small craft carried aboard a ship.
BOAT HOOK - A short shaft with a fitting at one end shaped to facilitate use in putting
a line over a piling, recovering an object dropped overboard, or in pushing or fending off.
BOOT TOP - A painted line that indicates the designed waterline.
BOW - The forward part of a boat.
BOW LINE - A docking line leading from the bow.
BOWLINE - A knot used to form a temporary loop in the end of a line.
BRIDGE - The location from which a vessel is steered and its speed
controlled. "Control Station" is really a more appropriate term for small craft.
BRIDLE - A line or wire secured at both ends in order to distribute a strain between
two points.
BRIGHTWORK - Varnished woodwork and/or polished metal.
BULKHEAD - A vertical partition separating compartments.
BUOY - An anchored float used for marking a position on the water or a hazard or a
shoal and for mooring.
BURDENED VESSEL - That vessel which, according to the applicable Navigation Rules,
must give way to the privileged vessel. The term has been superseded by the term "give-
way".
C
CABIN - A compartment for passengers or crew.
CAPSIZE - To turn over.
CAST OFF - To let go.
CATAMARAN - A twin-hulled boat, with hulls side by side.
CHAFING GEAR - Tubing or cloth wrapping used to protect a line from chafing on a
rough surface.
CHART - A map for use by navigators.
CHINE - The intersection of the bottom and sides of a flat or v-bottomed boat.
CHOCK - A fitting through which anchor or mooring lines are led. Usually U-shaped to
reduce chafe.
CLEAT - A fitting to which lines are made fast. The classic cleat to which lines are
belayed is approximately anvil-shaped.
CLOVE HITCH - A knot for temporarily fastening a line to a spar or piling.
COAMING - A vertical piece around the edge of a cockpit, hatch, etc. to prevent water
on deck from running below.
COCKPIT - An opening in the deck from which the boat is handled.
COIL - To lay a line down in circular turns.
COURSE - The direction in which a boat is steered.
CUDDY - A small shelter cabin in a boat.
CURRENT - The horizontal movement of water.
D
DEAD AHEAD - Directly ahead.
DEAD ASTERN - Directly aft.
DECK - A permanent covering over a compartment, hull or any part thereof.
DINGHY - A small open boat. A dinghy is often used as a tender for a larger craft.
DISPLACEMENT - The weight of water displaced by a floating vessel, thus, a boat's
weight.
DISPLACEMENT HULL - A type of hull that plows through the water, displacing a weight
of water equal to its own weight, even when more power is added.
DOCK - A protected water area in which vessels are moored.The term is often used to
denote a pier or a wharf.
DOLPHIN - A group of piles driven close together and bound with wire cables into a
single structure.
DRAFT - The depth of water a boat draws.
E
EBB - A receding current.
F
FATHOM - Six feet.
FENDER - A cushion, placed between boats, or between a boat and a pier, to prevent
damage.
FIGURE EIGHT KNOT - A knot in the form of a figure eight, placed in the end of a line
to prevent the line from passing through a grommet or a block.
FLARE - The outward curve of a vessel's sides near the bow. A distress signal.
