Maintains and monitors radio, sends and receives messages. Often maintains electronic navigation. Latest replaced with certified GO (Deck officer)

An absolute temperature scale. (

To prevent contact with an object while bringing the ship alongside.2. To push off when making a landing.

The part of a rotating element that counteracts any inherent thrust developed by the impellers.

Uncharted navigational danger that has been reported but has not been verified by survey.

To let out a line or sail slowly; to slacken or relieve tension on a line; to take pressure off.

A tiller or a wheel generally installed on the bridge or wheelhouse of a ship to turn the rudder during manoeuvering and navigation. It is in fact the steering wheel of the ship.

A line led to a sail, but is not currently in use. The line currently in use is known as the working sheet. Usually the working and lazy sheets change when the boat is tacked.

To go aboard the vessel; to put onboard a vessel.

A sailing ship with three to five masts, all of them square-rigged except the after mast, which is fore-and-aft rigged.

Said of a lighthouse not tended.

Slang for getting married. A splice joins two lines together permanently.

To repair, clean or paint the hull.

Cargo landed in excess of the quantity on manifest.

The compression of an air actuator (air spring) below its design height.

CFM flowing through the compressor inlet filter or inlet valve under rated conditions

(1) To throw, as to heave a line ashore. (2) An upward pull on a line; to lift (3) The rise and fall of a vessel in a seaway.

A fix taken by visually observing the location of known landmarks.

A support fixed on the front part of a chassis (which is retractable); used to support the front end of a chassis when the tractor has been removed.

A machine employing two or more stages.