Fair:
1. A smooth curve, usually referring to a line of the hull which has no deviations.
2. To make something flush.
3. A line is fair when it has a clear run.
4. A wind or current is fair when it offers an advantage to a boat.
Fall: The part of the tackle that is hauled upon.
Fairlead: A ring, hook or other device used to keep a line or chain running in the correct direction or to prevent it rubbing or fouling.
Fall off: To change the direction of sail so as to point in a direction that is more down wind. To bring the bow leeward. Also bear away, bear off or head down. This is the opposite of pointing up or heading up.
Fantail: Aft end of the ship, also known as the Poop Deck.
Fardage: Wood placed in bottom of ship to keep cargo dry. (Also see Dunnage)
Fast: Fastened or held firmly (fast aground: stuck on the seabed; made fast: tied securely).
Fathom (/?fæð?m/): A unit of length equal to 6 feet (1.8 m), roughly measured as the distance between a man's outstretched hands. Particularly used to measure depth.
Fender: An air or foam filled bumper used in boating to keep boats from banging into docks or each other.
Fetch:
1. The distance across water which a wind or waves have traveled.
2. To reach a mark without tacking.
Fid:
1. A tapered wooden tool used for separating the strands of rope for splicing.
2. A bar used to fix an upper mast in place.
Fife rail: A freestanding pinrail surrounding the base of a mast and used for securing that mast's sails' halyards with a series of belaying pins.
Figurehead: symbolic image at the head of a traditional sailing ship or early steamer.
Fireroom: The compartment in which the ship's boilers or furnaces are stoked and fired.
Fire ship: A ship loaded with flammable materials and explosives and sailed into an enemy port or fleet either already burning or ready to be set alight by its crew (who would then abandon it) in order to collide with and set fire to enemy ships.
First-rate: The classification for the largest sailing warships of the 17th through 19th centuries. They had 3 masts, 850+ crew and 100+ guns.
Fish:
1. To repair a mast or spar with a fillet of wood.
2. To secure an anchor on the side of the ship for sea (otherwise known as "catting".)
First Lieutenant: In the Royal Navy, the senior lieutenant on board; responsible to the Commander for the domestic affairs of the ship's company. Also known as 'Jimmy the One' or 'Number One'. Removes his cap when visiting the mess decks as token of respect for the privacy of the crew in those quarters. Officer i/c cables on the forecastle. In the U.S. Navy the senior person in charge of all Deck hands.
First Mate: The Second in command of a ship.
Fixed propeller: A propeller mounted on a rigid shaft protruding from the hull of a vessel, usually driven by an inboard motor; steering must be done using a rudder. See also outboard motor and sterndrive.
Flag hoist: A number of signal flags strung together to convey a message, e.g. 'England expects...'.
Flank: The maximum speed of a ship. Faster than "full speed".
Flare:
1. A curvature of the topsides outward towards the gunwale.
2. A pyrotechnic signalling device, usually used to indicate distress.
Flatback: A Great Lakes slang term for a vessel without any self unloading equipment.
Flemish: To coil a line that is not in use so that it lies flat on the deck.
Flotsam: Debris or cargo that remains afloat after a shipwreck. See also jetsam.
Fluke: The wedge-shaped part of an anchor's arms that digs into the bottom.
Fly by night: A large sail used only for sailing downwind, requiring little attention.
Folding propeller: A propeller with folding blades, furling to reduce drag on a sailing vessel when not in use.
Following sea: Wave or tidal movement going in the same direction as a ship
Foot:
1. The lower edge of any sail.
2. The bottom of a mast.
3. A measurement of 12 inches.
Footloose: If the foot of a sail is not secured properly, it is footloose, blowing around in the wind.
Footrope: Each yard on a square rigged sailing ship is equipped with a footrope for sailors to stand on while setting or stowing the sails
Force: See Beaufort scale.
Fore, forward, foreward (/?f?r?rd/, and often written "for'ard"): Towards the bow (of the vessel).
Forecastle: A partial deck, above the upper deck and at the head of the vessel; traditionally the sailors' living quarters. Pronounced /?fo?ks?l/. The name is derived from the castle fitted to bear archers in time of war.
Forefoot: The lower part of the stem of a ship.
Foremast jack: An enlisted sailor, one who is housed before the foremast.
Forestays: Long lines or cables, reaching from the bow of the vessel to the mast heads, used to support the mast.
Foul:
1. The opposite of clear. For instance, a rope is foul when it does nor run straight or smoothly, and an anchor is foul when it is caught on an obstruction.
2. A breach of racing rules.
3. An area of water treacherous to navigation due to many shallow obstructions such as reefs, sandbars, or many rocks, etc.
Foulies: A slang term for oilskins, the foul-weather clothing worn by sailors. See also oilskins.
Founder: To fill with water and sink ? Founder (Wiktionary)
Fourth rate: In the British Royal Navy, a fourth rate was, during the first half of the 18th century, a ship of the line mounting from 46 up to 60 guns.
Frame: A transverse structural member which gives the hull strength and shape. Wooden frames may be sawn, bent or laminated into shape. Planking is then fastened to the frames. A bent frame is called a timber.
Freeboard: The height of a ship's hull (excluding superstructure) above the waterline. The vertical distance from the current waterline to the lowest point on the highest continuous watertight deck. This usually varies from one part to another.
Full and by: Sailing into the wind (by), but not as close-hauled as might be possible, so as to make sure the sails are kept full. This provides a margin for error to avoid being taken aback (a serious risk for square-rigged vessels) in a tricky sea. Figuratively it implies getting on with the job but in a steady, relaxed way, without undue urgency or strain.
Furl: To roll or gather a sail against its mast or spar.
Futtocks: Pieces of timber that make up a large transverse frame.