Abaft - behind (on the boat) toward the stern.
Abeam - beside the boat, but not aboard.
Aboard - on a boat.
ABYC - American Boat and Yacht Council
                P.O. Box  806 Amityville, N.Y. 11701
Aft - toward the stern of a boat.
Aloft - above the hull; in the air.
Anti-ventilation plate - The horizontal plate just above the prop
                             (Sometimes called the anti-cavitation plate )
Amidships - near the middle of a boat.
Aqua-Dynamics- no such word (courtesy of Brian Espy)
Astern - behind the boat; to the rear.
Awash - barely floating; mostly submerged. or,
               ( what my boat needs)
Bail - the action of removing  water from the hold or
           bilge of the boat
Ballast - weight in a boat which affects the boats trim.
Beam - greatest width of a boat; the side of a boat.
Below - inside a boat.
Berth - a sleeping area in a boat; or, a place to moor a boat.
BIA - Boating Industry Association ( a part of history)
Bilge - the deepest part of the inside of a boat.
Bilge Rats- boat mechanics
Black Box - Tech talk for ignition module or
                    Electronic Control Module (ECM)
                    Also refereed to as, Power Pack and ignition
Blister - Used to describe water entry between the gel-coat
               and the fiberglass skin of a boat.
Bow - the front of a boat.
Bow Line - line going forward diagonally from a boat's bow to
                    secure it.
Bow steer - To "over trim" the boat to the point where the nose
                    of the boat starts to steer
Breast Line - line going sideways from a boat.
Bridge - upper helm station in some motorboats.
Buoy - floating aid to navigation.
Can - cylinder shaped buoy used for mooring
Capsize - turn upside down or (what increases as your boat
                   gets nicer.)
Cast Iron Genoa- a sail boat's engine
Cavitate- The entry of air into the propeller.
           Note: Testing has showed that excess vibration can
                     also cause cavitation and cavitation burns. 
                     The source of vibration can be mechanical and/or harmonic.
Chafe - wearing through of a line, sail, etc. from rubbing.
Charge Coil - Voltage generator used to power ignition modules.
                      (Mostly used on outboards.)
Chart - map of navigable waters.
Chine walk- Dangerously uncontrolled, side to side motion
                     associated with high speed operation
Cockpit - outside sitting area in a boat.
Cubic Inch Displacement (CID)- Speed
Current - horizontal movement on water.
Day Beacon -unlighted fixed aid to navigation.
Dead reckoning -  Determining your position by 
                                distance and course run
Displacement Hull - boat meant to move through the water,
                                 not skim over it.
Draft - least depth of water needed to allow a boat
             to clear the bottom.
Drift - speed of a current's flow.
DBWI - Driving a boat while intoxicated
Fairing Block- shim installed to adjust the angle of a mounted item.
Fair Lead - a line unobstructed between its terminals, such as
                  between a bow  chock and a piling.
Fender - protection for a boat.
Flapper - Short for flapper valve or Shutter valve, installed in the
                exhaust system of stern drive engines to prevent
                backwash of water into the engine if the engine were
                to shut down unexpectedly.
Forward - toward the bow; ahead.
Freeboard - height of a boat's gunwale above the water .
Fresh water Cooled - An engine that is cooled by anti-freeze
                                   run through a heat exchanger that is
                                   cooled by sea water.
Galley - a boat's kitchen. (Where the term "Galley Slave"
                 came from.)
Gel-Coat - colored, two part plastic finish on fiberglass boats.
Gimbal bearing- drive shaft support bearing located in
                              the gimbal housing.
Gimbal housing- supporting part of the stern drive, 
                              bolted to the transom
Gimbal ring - part of the stern drive that looks like a horse collar
                      and supports the stern drive and allows it to swivel
Ground Tackle - gear used for anchoring.
Gunwale - the top edge of a boat's hull.
GWL - gunwale length
Hatch - window mounted horizontally in the cabin roof.
Head - a boat's toilet; or the top corner of the sail.
Headstay - wire from the bow to the upper part of a sailboat's mast.
Heel - sideways learning of a boat due to the wind.
HEI - High energy Ignition
Helm - a boat's steering area; also the steering gear.
High Water - the tide's highest point before it starts to fall.
Hull - a boat's bottom shell.
Hull Speed - theoretical top speed for a displacement boat.
                     (primarily a sailboat.)
Knot - nautical mile (6,076 ft.) per hour  ( a measure of speed).
Lee of the Land - near a shore which provides protection
                            from wind and waves.
Lee Shore - land downwind of a boat.
Leeward - downwind; away from the source of wind.
Leeway - boat's sideways movement through the water, 
                due to the wind pushing it to leeward.
List - sideways tilt of a boat due to poor boat trim.
LOA - length overall, centerline length of hull including
            molded in pulpits and platforms
Make Way - to propel yourself through the water.
                    (What some boat mechanics do at the singles bar.)
Mooring - a place to secure a boat in the water.
MPI - Multi-port-Injection, as compared to,
           EFI - Electronic fuel Injectors, or
           TBI - Throttle body Injection
MSD - Marine Sanitary Device
Nautical Mile - 6076 feet; 1.15 statute miles.
Nun buoy- shaped like a rocket's nose cone.
NMMA - National Marine Manufacturers Association
Petcock - often used to describe the sea water drain valves
                 an inboard motor
Porpoise (porpoising) the rhythmic bouncing of the nose of a
                planing boat, often caused by over-trim
                 or hull irregularities
Port - "window" on a boat.
Port Side - a boat's left side.
Port (to) -  by a boat's left side.
Prop wash- The intersection of water, behind the boat,
                    initially displaced by hull movement through
                    the water.
Quarter - side of a boat abaft the beam.
Rectifier - In outboard motors, this item converts alternating
                current (AC) to direct current (DC).
Rode - line (chain or fiber) which joins an anchor to an anchored boat.
Rudder - flat board which redirects (aims) current or propeller
               wash to steer a boat.
Running Lights - lights to be displayed by a boat underway
                             at night or in restricted visibility.
Scope - ratio of anchor rode length to vertical distance from the
             anchor lead (chock or roller) to the bottom.
Scupper - water drain hole in the deck of a boat.
Sidelights - a boat's red and green lights.
Shift Interrupter - pressure sensitive switch used to electronically
                         slow the engine down when shifting gears.
Slack Water - the moment when a tidal current changes direction.
Sole - a boat's floor.
Spar - a type of buoy.
Splash-well - The pan area just in front of the transom on
                     outboard boats that helps keep back-wash
                     from entering the cockpit area.
Spring Line - line secured neat amidships and led ashore mostly
                    forward or aft, to keep a boat from surging
                    ahead or astern.
SSB - Single Side Band Radio (often a new option on VHF radios )
Stand Tide - the moment the tide changes direction up or down.
Starboard - on or along a boat's right side.
Starboard Side - a boat's right side.
Stern - a boat's back end.
Stern Light - white light which shows abaft a boat underway at night.
Stern Line - line leading diagonally aft from the stern to 
                     secure a boat.
Sternway - boat's backward movement through the water
                   or over the bottom.
Stringer - the internal hull bottom ribs used for structure
Stringer mount- Often used to describe early vintage OMC
                          sterndrive engine packages.
Strake- contour added to the outside hull bottom,
                to aid in performance
Swamp - to fill with water.
TCW - twin cycle, water cooled (as in TCW II and TCW 3 oils)
Tidal Current - horizontal flow of water due to the gravity of the
                         moon and the sun.
Tidal Range - how far the tide rises and falls.
Tide - vertical movement of water die to gravitational pull 
             of the moon and the sun.
Tiller - handle attached to the rudder, used to steer some boats.
TnT - Power Trim n Tilt
Transom - the outside flat part of a boat's stern.
Trigger - The electronic switch that replaced points.
               Often refereed to as a Trigger assembly.
Trim - fore and aft and side to side balance of a boat.
Trim fin - Small fin mounted to the gear case that helps
                   reduce steering torque.
Trim tab - Flat horizontal adjustable plate mounted to the
                  transom that helps adjust bow up and bow down angle
True Bearing - Bearing or direction taken relative to true North
Vertical Drive - often used to describe the inboard outboard
                           stern drive.
Wake - waves made by a boat's movement through the water.
             ( the disturbance your wife makes
                 when you tell her your going boating.)
Walter Drive - V drive inboard transmission
Windward - toward or into the source of the wind.
WLL - water line length
Yard- a spar on a mast from which sails are set.
Yardarm - The outermost tips of the yard: outboard from
                   the attachments for the lifts.

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