Grating - Light platform or walkway built up of metal bars, used for access to machinery.
Category: - Maritime

Graving Dock - An arrangement for getting vessels out of the water so that bottom work can be done. Usually a slip is dug in the shore, a vessel is floated in, a wall is placed across the open end of the slip and the water is pumped out of the 'tank'. Often used for very heavy objects.
Category: - Maritime

Great Circle Route - The shortest path (on the surface) between two points on the globe, used for ship navigation.
Category: - GIS

Great Lakes Ship - Cargo ship developed to carry raw materials and manufactured goods on the Great Lakes. Most carry bulk cargoes of grain, iron ore or coal.
Category: - Maritime

Grid Cell - A single cell in a rectangular grid.
Category: - GIS

Grid Extent - The ground or map extent of the area corresponding to a grid.
Category: - GIS

Griffon - The Griffon (CH-146) is the newest edition to the military aircraft fleet. It is a variant of the civilian Bell 412. It is painted camouflage colors because its primary mission is support to the army and SAR support to Canada's F18 fighter squadrons, although it will readily respond to any SAR incident. The Griffon can be equipped with forward looking infrared (FLIR) which enables it to seek out aircraft and personnel by the heat they give off, making it an ideal search aircraft. In its SAR configuration, the Griffon's crew consists of two Pilots, one Flight Engineer and one Search and Rescue Technician.
Category: - SAR

Gross Domestic Product - The total value of goods and services produced by a nation over a given period, usually 1 year.
Category: - General

Gross National Product - Gross Domestic Product (GDP) plus the net income accruing from foreign sources.
Category: - General

Gross Registered Ton - "(GRT) A measure of vessel capacity (in cubic feet) of the space within the hull, and of enclosed spaces above deck, available for cargo, stores, fuel, passengers and crew, with certain exclusions. One hundred cubic feet is equivalent to one gross ton. "
Category: - Maritime