To let go.

The volume of a substance passing a point per unit time (e.g., meters per second, gallons per hour, etc.).

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.

A fitting around the propeller shaft to keep the bearing lubricated and to keep water out of the boat.

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

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 ...

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

A propulsion system for boats with an inboard engine operating an exterior drive, with drive shaft, gears, and propeller; also called stern-drive and inboard/outboard.

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

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

Method of securing a line around a spar by taking the standing part around the spar, then a half hitch around itself and the end tucked three or four times around its own part.

An old method of cleaning a vessels bottom by burning off weed, barnacles or other growth while the vessel was in dry dock or careened. Breaming was also known as graving.

A form of steam engine where a piston moves back and forth inside a cylinder, transmitting its motion to a driving shaft by a connecting rod and crank.

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

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

A small flat boat, usually inflatable.

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

To approach something from upwind

One which blows across a boat's side

When a ship's head or stern pitches suddenly and violently into the trough of the sea.