Dyneema

A brand of ultra-high-molecular-weight polyethylene (UHMWPE) fibre; as strong as steel wire but a fraction of the weight, now widely used for halyards, sheets, and even standing rigging.

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A stern-mounted arch or pair of arms fitted with tackle so a tender can be lifted clear of…

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The mostly horizontal upper surface of the hull.

Dead downwind

Sailing directly with the wind astern, 180° from its source.

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A long cone or series of small cones streamed on a bridle from the stern in very heavy wea…

Dock

A quay, pontoon, or berth where a vessel ties up — and also the act of bringing her alongs…

Draft

The vertical distance from the waterline to the deepest part of the keel — the minimum wat…

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