Great Circle

The shortest path between two points on the Earth's surface — an arc of a circle whose plane passes through the centre of the Earth. Used for long ocean passages.

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Related G-terms

Gybe

See jibe — a turn in which the stern passes through the wind.

Grommet

A reinforced ring — usually brass or stainless — set into a sail or cover to accept a line…

Gaff

On a four-sided fore-and-aft sail, the spar that supports the sail's upper (head) edge.

Gooseneck

The articulated fitting that joins the forward end of the boom to the mast, allowing the b…

Ground tackle

The collective name for the anchor and its rode (chain, warp, swivels, and shackles).

Give way vessel

Under the COLREGs, the vessel that is required to keep out of the way of another when risk…

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