bowline

bowline (pron. bolin as in no).
1. A knot tied in such a way as to produce an eye, or loop, in the end of a rope. It is a knot with many uses at sea, whether to join two large hawsers together, with one bowline tied with its eye inside the eye of the other, or tied in the end of a hawser to provide a loop for dropping over a bollard. It is a knot which will never slip and cannot jam. Variants of this knot are a running bowline, where the knot is tied around the bight of the rope to form a noose, and a bowline on the bight, where the knot is made with the bight of the rope to produce two eyes. This variant is often used to form a temporary boatswain's chair when a man is needed to work aloft.

2. The name of the rope attached with a bowline to, and leading forward from, a bridle between cringles on the leeches of sails in a square-rigged ship. Its purpose, when hauled hard in, is to keep the weather edge of the sail taut and steady when the ship is close hauled to the wind. Thus a square-rigged ship is said to ‘sail on a bowline’, or ‘stand on a taut bowline’, when it is being sailed as close to the wind as possible.