To luff or luff up is to head into the wind, causing sails to flutter.

Similar to a Barber hauler, a twing adjusts the angle of sheeting.

Used to describe a light that blinks on and off, where the period of light is shorter than the period of darkness separating the flashes.

A strong pair of iron, steel or wooden posts on a ship's deck, around which ropes or cables are wound and held fast.

Certificate given to a ship arriving from a foreign port, by the port's health officer, indicating that there are no cases of disease aboard the ship and the health of all on board is good.

Originally meant "to stow cargo". Now, means "to search a ship carefully and thoroughly".

A fishing vessel designed to tow a trawl for catching bottom fish.

Is a unit of work equal to 33,000 foot pounds per minute, 550 foot pounds per second, or 746 Watts.

A change in the wind direction.

A small flat bottomed boat square at either end.

A harbor restriction placed on a ship which has an infectious disease on board, or which has arrived from a country where such a disease is prevalent. The crew may not go ashore until the ship is granted pratique.

A heavy longitudinal timber placed over the keel in a ship's stern through which the propeller shaft passes.

A slang name for a bullying officer on a ship.

Sailor's name for a block of sandstone used for scrubbing the wooden decks of a ship; seamen had to get down on their knees to use them. Large holystones were known as "Bibles", while smaller blocks to reach awkward places were known as "Prayer Books" ...

(1) A small wooden cask in which grog was carried. (2) A type of marine steam reciprocating engine where two engines were used together on the same propeller shaft.

A Latin term meaning "For the sake of form."

When a boat has two separate fins, instead of a centerboard or keel, they are referred to as bilge boards.

A slide which travels on a track to which the mainsheet may be attached. The sail shape can be subtly altered by changing the mainsheet position on the traveler.

A book containing the official record of a ship's activities together with remarks concerning the state of the weather, etc.