The Collaborative International Dictionary of English v.0.48:

Knot \Knot\ (n[o^]t), n. [OE. knot, knotte, AS. cnotta; akin to
   D. knot, OHG. chnodo, chnoto, G. knoten, Icel. kn[=u]tr, Sw.
   knut, Dan. knude, and perh. to L. nodus. Cf. Knout,
   Knit.]
   1.
      (a) A fastening together of the parts or ends of one or
          more threads, cords, ropes, etc., by any one of
          various ways of tying or entangling.
      (b) A lump or loop formed in a thread, cord, rope. etc.,
          as at the end, by tying or interweaving it upon
          itself.
      (c) An ornamental tie, as of a ribbon.
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   Note: The names of knots vary according to the manner of
         their making, or the use for which they are intended;
         as, dowknot, reef knot, stopper knot, diamond knot,
         etc.
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   2. A bond of union; a connection; a tie. "With nuptial knot."
      --Shak.
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            Ere we knit the knot that can never be loosed. --Bp.
                                                  Hall.
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   3. Something not easily solved; an intricacy; a difficulty; a
      perplexity; a problem.
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            Knots worthy of solution.             --Cowper.
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            A man shall be perplexed with knots, and problems of
            business, and contrary affairs.       --South.
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   4. A figure the lines of which are interlaced or intricately
      interwoven, as in embroidery, gardening, etc. "Garden
      knots." --Bacon.
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            Flowers worthy of paradise, which, not nice art
            In beds and curious knots, but nature boon
            Poured forth profuse on hill, and dale, and plain.
                                                  --Milton.
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   5. A cluster of persons or things; a collection; a group; a
      hand; a clique; as, a knot of politicians. "Knots of
      talk." --Tennyson.
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            His ancient knot of dangerous adversaries. --Shak.
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            Palms in cluster, knots of Paradise.  --Tennyson.
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            As they sat together in small, separate knots, they
            discussed doctrinal and metaphysical points of
            belief.                               --Sir W.
                                                  Scott.
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   6. A portion of a branch of a tree that forms a mass of woody
      fiber running at an angle with the grain of the main stock
      and making a hard place in the timber. A loose knot is
      generally the remains of a dead branch of a tree covered
      by later woody growth.
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   7. A knob, lump, swelling, or protuberance.
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            With lips serenely placid, felt the knot
            Climb in her throat.                  --Tennyson.
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   8. A protuberant joint in a plant.
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   9. The point on which the action of a story depends; the gist
      of a matter. [Obs.]
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            I shoulde to the knotte condescend,
            And maken of her walking soon an end. --Chaucer.
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   10. (Mech.) See Node.
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   11. (Naut.)
       (a) A division of the log line, serving to measure the
           rate of the vessel's motion. Each knot on the line
           bears the same proportion to a mile that thirty
           seconds do to an hour. The number of knots which run
           off from the reel in half a minute, therefore, shows
           the number of miles the vessel sails in an hour.
           Hence:
       (b) A nautical mile, or 6080.27 feet; as, when a ship
           goes nautical eight miles an hour, her speed is said
           to be eight knots.
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   12. A kind of epaulet. See Shoulder knot.
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   13. (Zool.) A sandpiper (Tringa canutus), found in the
       northern parts of all the continents, in summer. It is
       grayish or ashy above, with the rump and upper tail
       coverts white, barred with dusky. The lower parts are
       pale brown, with the flanks and under tail coverts white.
       When fat it is prized by epicures. Called also dunne.
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   Note: The name is said to be derived from King Canute, this
         bird being a favorite article of food with him.
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               The knot that called was Canutus' bird of old,
               Of that great king of Danes his name that still
               doth hold,
               His appetite to please that far and near was
               sought.                            --Drayton.
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