The two sides of a block. (2) Pieces of timber attached to the mast below the masthead to support the trestle trees.

To coil down the tail of a line on deck to present a neat appearance.

Specially designed for the transport of chemicals.

The crew's term for the chief engineer.

The senior engineer officer responsible for the satisfactory working and upkeep of the main and auxiliary machinery and boiler plant on board ship.

Another term for first mate.

The operation of pressing oakum into a seam as a temporary measure until the seam can be properly caulked.

a filter intended to prevent only large particles from entering a component immediately downstream.

A hand held pneumatic tool. Designed to chip masonry, plaster, concrete etc.

A chemical element that is a heavy strong smelling greenish yellow imitating gas used as a bleach, oxidizing agent and disinfectant. Found in some ambient air conditions.

Compounds containing chlorine, fluorine or bromine, used as aerosol propellants, refrigerants, foaming agents and solvents and which, on decomposition by sunlight, produce oxides of chlorine responsible for the removal of ozone from the stratosphere.

To place pieces of dunnage in between pieces of cargo in order to prevent shifting of the cargo.

A piece of wood or other material placed at the side of cargo to prevent rolling or moving sideways.

A heavy wooden or metal fitting secured on a deck or on a dock, with jaws, used for the lead or to guide lines or cables.

When a line is pulled as tight as is can go, as when two blocks are pulled together so that no further movement is possible (also known as "Two blocked").

This term is used for turbo compressors and represents the maximum flow condition. It is sometimes also referred to as stonewalling.

To temporarily stop all movement of a line through a block by placing the hauling part across the sheave of the block. This jams the sheave and holds it tight, and a pull on the hauling part will release it.

The falls foul in a block. The falls may be chocked or jammed intentionally for a temporary securing (holding).

Small, steep disorderly waves at rapid intervals.

An imaginary line drawn between the luff and leech of a sail. The chord depth is an imaginary line drawn to the deepest part of the sail from the chord. The ratio of chord depth to chord length represents the sail's draft - a high ratio indicates a full s ...