A control line that adjusts tension along the foot of the sail, pulling the clew away from the tack; used to maintain proper sail shape.

Invisible waves in the electromagnetic spectrum that are used to communicate (radio) - and navigate (radar).

(1) When two or more boats tie up alongside each other. (2) Overlapping of edges of two ice-floes, so that one floe is partly supported by the other.

The direction at right angles to a ship's heading or the line of her keel

Across the width of a boat. Also Athwartships.

The dimensionless number obtained when the difference between maximum and minimum instantaneous shaft speeds during one period is divided by the arithmetic mean of these two.

To put a narrow piece of canvas around it after it has been wormed, and before it has been served.

A knot used to temporarily shorten a line.

Filter, Regulator and lubricator sometimes combined in one unit

Old name for bunting from which signal and other flags were made.

A mop, formed of old rope, used for cleaning and drying decks.

Are load carrying machine elements permitting some degree of motion in which the lubricant is air or some other gas.

On the land or aground.

The ratio of the actual water-vapor partial pressure to its saturation pressure at the same temperature. (considered only with atmospheric air).

The top of a wave.

Go to bed without undressing.

A disturbance of surface water by conflicting current or by winds.

Speed Over Ground, speed relative to bottom.

At or towards the stern or rear of a ship.

The warehouse or public stores to which samples of imported goods are taken to be inspected, analyzed, weighed, etc. by examiners or appraisers.