• Webster's Revised Unabridged Dictionary
    • n Jackstay (Naut) A rail of wood or iron stretching along a yard of a vessel, to which the sails are fastened.
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Century Dictionary and Cyclopedia
    • n jackstay Nautical: One of a set of ropes, iron rods, or strips of wood attached to a yard or gaff for bending a square sail to.
    • n jackstay A rod or rope running up and down on the forward side of a mast, on which the square-sail yard travels; a traveler.
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