The Collaborative International Dictionary of English v.0.48:

Down \Down\, adv. [For older adown, AS. ad[=u]n, ad[=u]ne,
   prop., from or off the hill. See 3d Down, and cf. Adown,
   and cf. Adown.]
   1. In the direction of gravity or toward the center of the
      earth; toward or in a lower place or position; below; --
      the opposite of up.
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   2. Hence, in many derived uses, as:
      (a) From a higher to a lower position, literally or
          figuratively; in a descending direction; from the top
          of an ascent; from an upright position; to the ground
          or floor; to or into a lower or an inferior condition;
          as, into a state of humility, disgrace, misery, and
          the like; into a state of rest; -- used with verbs
          indicating motion.
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                It will be rain to-night. Let it come down.
                                                  --Shak.
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                I sit me down beside the hazel grove.
                                                  --Tennyson.
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                And that drags down his life.     --Tennyson.
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                There is not a more melancholy object in the
                learned world than a man who has written himself
                down.                             --Addison.
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                The French . . . shone down [i. e., outshone]
                the English.                      --Shak.
      (b) In a low or the lowest position, literally or
          figuratively; at the bottom of a descent; below the
          horizon; on the ground; in a condition of humility,
          dejection, misery, and the like; in a state of quiet.
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                I was down and out of breath.     --Shak.
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                The moon is down; I have not heard the clock.
                                                  --Shak.
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                He that is down needs fear no fall. --Bunyan.
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   3. From a remoter or higher antiquity.
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            Venerable men! you have come down to us from a
            former generation.                    --D. Webster.
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   4. From a greater to a less bulk, or from a thinner to a
      thicker consistence; as, to boil down in cookery, or in
      making decoctions. --Arbuthnot.
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   Note: Down is sometimes used elliptically, standing for go
         down, come down, tear down, take down, put down, haul
         down, pay down, and the like, especially in command or
         exclamation.

               Down, therefore, and beg mercy of the duke.
                                                  --Shak.
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               If he be hungry more than wanton, bread alone
               will down.                         --Locke.
         Down is also used intensively; as, to be loaded down;
         to fall down; to hang down; to drop down; to pay down.

               The temple of Her[`e] at Argos was burnt down.
                                                  --Jowett
                                                  (Thucyd.).
         Down, as well as up, is sometimes used in a
         conventional sense; as, down East.

               Persons in London say down to Scotland, etc., and
               those in the provinces, up to London.
                                                  --Stormonth.
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   Down helm (Naut.), an order to the helmsman to put the helm
      to leeward.

   Down on or Down upon (joined with a verb indicating
      motion, as go, come, pounce), to attack, implying the idea
      of threatening power.
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            Come down upon us with a mighty power. --Shak.

   Down with, take down, throw down, put down; -- used in
      energetic command, often by people aroused in crowds,
      referring to people, laws, buildings, etc.; as, down with
      the king! "Down with the palace; fire it." --Dryden.

   To be down on, to dislike and treat harshly. [Slang, U.S.]


   To cry down. See under Cry, v. t.

   To cut down. See under Cut, v. t.

   Up and down, with rising and falling motion; to and fro;
      hither and thither; everywhere. "Let them wander up and
      down." --Ps. lix. 15.
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