Naut. Short for WALL-KNOT.

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1834.  Marryat, P. Simple, vi. ‘How is this to be finished off sir?’ inquired a sailor of the boatswain. ‘Why,… it must be with a double wall.’

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c. 1860.  H. Stuart, Seaman’s Catech., 30. Make a single wall. Ibid., 56. A ‘double wall’ or deck stopper-knot is made … close up to the wall.

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1884.  Knight, Dict. Mech., Suppl., Wall and Crown. This knot should be finished with a crown.

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