Aft : the Back of the ship/boat
Afterguard: Body of men working the aftersails from quarterdeck and poop.
Battery: (1) Section of a broadside commanded by a lieutenant or midshipman. (2) Gun position on land.
Beam: Widest part of a ship.
Between the devil and the deep blue sea: The devil isn't Satan but the seam in the planking on the waterline. If a sailor found himself stuck there, he was in a pretty precarious position.
Bowspirit: Spar projecting over a ship's bow and spreading parts of the standing rigging and the jibs.
Brigs: Two-masted, square-rigged vessel with a staysail on a boom on the aftermast.
Broadside: (1) The complete battery mounted on one side of a ship. (2) The simultaneous firing of all these guns.
Bulkhead: Vertical partition below decks.
Burgoo: A kind of portridge.
By and large: The expression dates from the days of square-rigged vessels. "By the wind" meant that the wind was before the beam: "sailing large" meant it was lagging behind. "By and large", therefore, implies a general balance between extremes.
Carronade: A short light cannon firing a disproportionately heavy ball at a low velocity.
Coxswain: Seaman in permanent charge of a ship's boat.
Cutter: (1) One-masted vessel rigged with a gaff mainsail, topsail, headsails and usually a square topsail. (2) Short ship's boat.
Davy Jones's Locker: Seamen's slang for the bottom of the sea. There are several theories as to the origin of the expression: One is that Davy Jones was the owner of a sixteenth-century London pub where unwary sailors were drugged and put in lockers, and then awoke aboard ship to find they had been press-ganged into the Navy.
In the doldrums: Being inactive or depressed - deriving from the doldrums near the equator where calm conditions prevail and sailing ships were often becalmed for days or weeks.
Flagship: Ship carrying an admiral, and therefore his flag.
Forecastle: Small deck built over the forward part of the main deck.
Foremast: Foremost of a ship's three masts.
Frigate: Fifth or Sixth "rate" ship (ships were rated by the number of cannon they carried), most often with 32-38 cannon. Everyone but the captain lived on the unarmed "gundeck" at the waterline.
Gaff: Spar extending the heads of certain fore-and-aft sails.
To run the gauntlet: Now meaning to go through an unpleasant experience, it derives from a naval and military punishment that became prominent during the Thirty Years War (1618-48), when an offender was forced to proceed between two lines of men who would attack him with clubs, whips or knotted cords. Derives from the Swedish "gata" meaning road, and "lopp", meaning course.
Heads: The crew's latrines, an open grating each side of the base of the bowsprit.
League: Three nautical miles.
Longboat: Largest of a ship's boats.
Maelstrom: Used to denote a confused turmoil, it was originally the name given to strong currents in the waters of Norway's Lofoten Islands. Derives from the Dutch "malem"-to grind-and "stroom", meaning stream.
Mainmast: Tallest mast, the central one of a ship.
Mast: (1) The complete foremast, mainmast or mizzenmast. (2) A section of these; as foremast, foretopmast, foretopgallant. Topmasts and topgallantmasts could be removed in heavy weather.
Mizzenmast: The aftermost (rear) mast of a ship or ketch.
Orlop: The lowest deck of a ship, lying above the hold and below the waterline.
Part of a ship: One of a number of parties into which each watch was divided.
To take someone down a peg or two: Ships' flags were raised or lowered using pegs. To lower a flag meant to surrender. To 'nail your colours [flag] to the mast', on the other hand, is a declaration of firm allegiance and intent to carry on regardless.
Pinnance: Eight-oared ship's boat.
Plain sailing: Originally "plane sailing", a simplified method of determining the course of a ship by assuming the earth is flat: lines of longitude and latitude are considered as perpendiculars. Accurate for short distances.
Poop: The highest aftermost deck of a ship, on the largest ships.
Privateer: Privately-owned ship of war, licensed by letter of marque (from the Lord High Admiral) to carry arms against a named enemy nation to their owners' profit.
Quarterdeck: Raised deck above the main deck; partly below the poop deck, if present. Often running half the length of a ship, it was reserved for officers.
Rating: (1) The station a person holds on the ship's books. (2) The rate of a ship. (3) Loosely, ordinary seamen.
No room to swing a cat: Denoting a cramped space, the expression is thought to derive from the days when a cat-o'-nine tails -- a lash with nine knotted lines (hence a cat has nine lives) - was used to flog disobedient sailors. The punishment was carried out on deck as conditions below were too cramped. Other sources suggest that the 'cat' was originally a sailor's hammock or cot.
Royal: A square sail and mast above the topgallant.
Ship: Exclusively a square-rigged vessel with three (later, more) articulated masts.
Ship-of-the-line: Also known as a line-of-battle ship. A man-of-war large enough to lie in the line of battle. By the 1790s, this meant in practice ships from the first to third rate.
Shipshape and Bristol fashion: Derives from the days when Bristol was a major trading port with a reputation for efficiency.
Sloop: (1) Any naval vessel commanded by a Commander, usually a small ship with 12-20 cannon. (2) A small, one-masted fore-and-aft vessel.
Spar: A length of timber, used in masting and rigging to spread sails.
Taffrail: The after-rail at a ship's stern.
Tender: An auxiliary vessel or boat.
Topgallant: The mast and sails above the topmast, itself above the mainmast on an articulated mast.
Topman: A seaman who works aloft.
Wardroom: Lieutenants' and warrant officers' mess. In a frigate it was aft, on the waterline, below the captain's cabin.
Watch: (1) One of the seven divisions of the nautical day. (2) One of the two or three divisions into which seaman were divided for work and leisure.
To take the wind out of someone's sails: If a square-rigged ship sailed too close to another on the windward side, it would deprive the latter of wind and therefore the power to move.
Windward: The direction from which the wind is blowing.
Yard: A long spar across a mast to support and spread a sail.
* I am still trying to work out the kinks :@ (