The curved part of a ship's hull where the side and the flat bottom meet.

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

A mechanical barometer used to measure air pressure for warnings of changing weather.

Imaginary lines drawn through the north and south poles on the globe used to measure distance east and west of the prime meridian at Greenwich, England (designated as 0

A short piece of line spliced into the end of the clapper by which the bell is struck. Traditionally it is finished off with a double wall knot crowned in its end.

Any object used to increase the drag of a boat and slow her down. Typically shaped like a parachute or cone opened underwater, drogues decrease a boat's speed in heavy weather. Also see sea anchor.

Money paid by shipper to Master of ship for diligence in care of cargo. Not now paid to Master, but added to freight. Amount was usually about 1% of freight.

A device which operates compressors in sequence according to a programmed schedule.

Pieces of plank bolted to the outer end of the bowsprit, to reeve the foretopmast stays through.

A pole used as part of the sailboat rigging, such as masts, booms, gaffs, yards, etc. A vertical spar is a mast.

A horseshoe-shaped or circular reef of coral surrounding a lagoon.

Where the water and sky or ground and sky appear to intersect.

A gas produced by many fruits and vegetables that accelerates the ripening and aging processes.

Complete encirclement of a cleat, bollard, pin or winch by a line.

see Watch

Temperature at which condesation first occurs and moisture is formed.

The largest circle which can be inscribed on a sphere by a plane that cuts through the center of the sphere. On the earth, the equator is a great circle, as are all the meridians of longitude which pass through both poles. The shortest distance between tw ...

: Regular ship shaped vessel, production ship. Positioned by anchors or dynamic positioning. Has its own propulsion machinery.

The standard atmosphere is defined as the pressure exerted by a column of mercury 760 mm high with a density of 13,595 g/cm

Anchor cable is caught around the fluke or an object is caught around the anchor .