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

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.

The alternating motion of a boat, leaning alternately to port and starboard; the motion of a boat about its fore-and-aft axis.

A ring-shaped fitting into which the rudder pintle is inserted which allows the rudder to pivot.

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

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

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.

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

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

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

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.

To keep close.

One which blows across a boat's side

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

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

Sailing with the motor on and in gear

To approach something from upwind

A small flat boat, usually inflatable.