Have you ever found yourself in a conversation with a veteran boater or a boat salesperson, nodding your head knowingly as they spoke, without having a clue what they’re talking about? Nautical jargon fills the air during boat show season and, if you are relatively new to boating, it can be like trying to understand a foreign language.
The following is a brief overview of some of the most common terms in the boating vernacular to assist in building your nautical-speak vocabulary. Be patient with yourself, time and repetition will etch these into your memory – and eventually you’ll be able to hold your own with the old salts at the marina and during the shows.
The main body of a boat is the hull, consisting of a metal or composite shell fastened to and/or integrated with structural components for strength and buoyancy. Inside, the deck covers the hull, reinforcing the framework, keeping water out of the lower portions of the hull, and is the “floor” of the boat.
The bilge is the lowest part of the hull, under the deck and below the waterline.
At the front of the boat, the hull sides come together to create the bow; the stern is where the sides of the hull terminate at the transom in the back of the boat.
The intersection of the bottom and the side of the hull is the chine; the uppermost part of the hull side is the gunwale (pronounced gunnel).
Engine throttle and shift controls, instrumentation, and the steering wheel (or outboard tiller arm) are at the helm.
Locations and Directions
The bow is the front of the boat; the stern is the back of the boat. Looking towards the bow, the right side of the boat is the starboard side, and the left side is the port side of the vessel. The right front side is the starboard bow; the port bow is the left front side of the boat.
At the stern, facing the front of the boat, the starboard quarter is the right rear area; the port quarter is the left rear area.
Forward (or fore) is frontward; aft is rearward. Walking to the bow is going forward; making your way to the stern is going aft.
Driving the boat forward is going ahead; moving the boat backwards (traveling in reverse) is going astern.
The centerline is an imaginary line from bow to stern, down the middle of a boat. Outboard is from the centerline towards either side of the craft; conversely, inboard is from the boat’s side towards the centerline. (Outboard and inboard are also types of propulsion systems; we’re not discussing them today).
Amidships (or midships) is the center area of the boat. The port beam is the left center side, and the starboard beam is the right center side. Athwartships describes lines, gear, or anything else situated from one side of the boat to the other.
Length Overall (LOA) is the distance from the most forward and aft parts of the boat, as measured straight along the centerline. Read the fine print in the boat manufacturer’s catalog or owner’s manual – the LOA may or may not include the swim platform and/or bow pulpit (if so equipped).
The widest part of the hull is the beam, and depending on the hull style, the beam measurement could be at the stern, amidships, or nearly anywhere else.
Freeboard is the distance from the surface of the water at the boat’s true waterline (with a typical load in the boat) to the gunwale, measured where the boat sits lowest in the water (often near the stern).
This one is important, so take notes. Draft is how deep your boat sits in the water, determined by the measurement from the (loaded) waterline to the lowest appendage under the hull (usually the tip of the outboard’s skeg, with the engine trimmed down). For example, the manufacturer of a certain 31-foot center console rigged with a pair of Yamaha 250 hp outboards states that the boat’s draft is two feet, 10 inches, with the engines trimmed down; however that number may not reflect draft of the boat loaded for an offshore fishing excursion.
Another way to define draft is how much water depth is necessary to float the boat. Around the docks, you may hear someone say a particular boat draws ___ feet of water – a different way of expressing a boat’s draft.
Keep in mind that if your boat’s draft is say, two feet, you’ll need about three feet of water to operate the vessel. Remember, by the time the depth finder displays its reading, you’ve already traveled past that point where the reading was taken. In addition, wave action can change water depth – deeper at the crests and shallower in the troughs of the waves.
Knowing the actual draft of your boat, and driving with that in the back of your mind can prevent the costly and potentially tragic results of running aground – hitting the bottom of the lake with the boat or engine.
Other Items of Interest
The dry weight of the boat is a specification provided by the manufacturer – often simply the weight of the bare hull, without fluids (fuel, oil, livewells full, etc.), power, or rigging (batteries, steering system, engine controls). Some builders provide a weight figure including the outboard(s), but calculating actual real-world boat weight is tough.
The best way we know of determining boat weight is to tow the boat (or a sister ship) to a certified truck scale, weigh the boat and trailer, and then deduct the known trailer weight to get the boat’s weight – or very close to it.
Boat speed is expressed in knots (kts), nautical miles per hour, or statute (land) miles-per-hour (mph). A knot is one nautical mile (6,076 feet), and equal to one minute of latitude; a statute mile is slightly shorter (5,280 feet). One nautical mile equates to roughly 1.15 statute miles.
Yes, we’ve covered a lot of material, and no, you probably won’t retain much initially – it will require re-reading, and applying the terms to your own boat for the information to stick.
Don’t be shy about asking questions when other boaters mention something you don’t know; most will be glad to share their experiences with you.