The Collaborative International Dictionary of English v.0.48:

dragon \drag"on\ (dr[a^]g"[u^]n), n. [F. dragon, L. draco, fr.
   Gr. dra`kwn, prob. fr. de`rkesqai, dra`kein, to look (akin to
   Skr. dar[,c] to see), and so called from its terrible eyes.
   Cf. Drake a dragon, Dragoon.]
   1. (Myth.) A fabulous animal, generally represented as a
      monstrous winged serpent or lizard, with a crested head
      and enormous claws, and regarded as very powerful and
      ferocious.
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            The dragons which appear in early paintings and
            sculptures are invariably representations of a
            winged crocodile.                     --Fairholt.
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   Note: In Scripture the term dragon refers to any great
         monster, whether of the land or sea, usually to some
         kind of serpent or reptile, sometimes to land serpents
         of a powerful and deadly kind. It is also applied
         metaphorically to Satan.
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               Thou breakest the heads of the dragons in the
               waters.                            -- Ps. lxxiv.
                                                  13.
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               Thou shalt tread upon the lion and adder; the
               young lion and the dragon shalt thou trample
               under feet.                        -- Ps. xci.
                                                  13.
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               He laid hold on the dragon, that old serpent,
               which is the Devil and Satan, and bound him a
               thousand years.                    --Rev. xx. 2.
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   2. A fierce, violent person, esp. a woman. --Johnson.
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   3. (Astron.) A constellation of the northern hemisphere
      figured as a dragon; Draco.
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   4. A luminous exhalation from marshy grounds, seeming to move
      through the air as a winged serpent.
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   5. (Mil. Antiq.) A short musket hooked to a swivel attached
      to a soldier's belt; -- so called from a representation of
      a dragon's head at the muzzle. --Fairholt.
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   6. (Zool.) A small arboreal lizard of the genus Draco, of
      several species, found in the East Indies and Southern
      Asia. Five or six of the hind ribs, on each side, are
      prolonged and covered with weblike skin, forming a sort of
      wing. These prolongations aid them in making long leaps
      from tree to tree. Called also flying lizard.
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   7. (Zool.) A variety of carrier pigeon.
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   8. (Her.) A fabulous winged creature, sometimes borne as a
      charge in a coat of arms.
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   Note: Dragon is often used adjectively, or in combination, in
         the sense of relating to, resembling, or characteristic
         of, a dragon.
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   Dragon arum (Bot.), the name of several species of
      Aris[ae]ma, a genus of plants having a spathe and
      spadix. See Dragon root(below).

   Dragon fish (Zool.), the dragonet.

   Dragon fly (Zool.), any insect of the family
      Libellulid[ae]. They have finely formed, large and
      strongly reticulated wings, a large head with enormous
      eyes, and a long body; -- called also mosquito hawks.
      Their larv[ae] are aquatic and insectivorous.

   Dragon root (Bot.), an American aroid plant (Aris[ae]ma
      Dracontium); green dragon.

   Dragon's blood, a resinous substance obtained from the
      fruit of several species of Calamus, esp. from Calamus
      Rotang and Calamus Draco, growing in the East Indies. A
      substance known as dragon's blood is obtained by exudation
      from Drac[ae]na Draco; also from Pterocarpus Draco, a
      tree of the West Indies and South America. The color is
      red, or a dark brownish red, and it is used chiefly for
      coloring varnishes, marbles, etc. Called also Cinnabar
      Gr[ae]corum.

   Dragon's head.
      (a) (Bot.) A plant of several species of the genus
          Dracocephalum. They are perennial herbs closely
          allied to the common catnip.
      (b) (Astron.) The ascending node of a planet, indicated,
          chiefly in almanacs, by the symbol ?. The deviation
          from the ecliptic made by a planet in passing from one
          node to the other seems, according to the fancy of
          some, to make a figure like that of a dragon, whose
          belly is where there is the greatest latitude; the
          intersections representing the head and tail; -- from
          which resemblance the denomination arises. --Encyc.
          Brit.

   Dragon shell (Zool.), a species of limpet.

   Dragon's skin, fossil stems whose leaf scars somewhat
      resemble the scales of reptiles; -- a name used by miners
      and quarrymen. --Stormonth.

   Dragon's tail (Astron.), the descending node of a planet,
      indicated by the symbol ?. See Dragon's head (above).

   Dragon's wort (Bot.), a plant of the genus Artemisia
      (Artemisia dracunculus).

   Dragon tree (Bot.), a West African liliaceous tree
      (Drac[ae]na Draco), yielding one of the resins called
      dragon's blood. See Drac[ae]na.

   Dragon water, a medicinal remedy very popular in the
      earlier half of the 17th century. "Dragon water may do
      good upon him." --Randolph (1640).

   Flying dragon, a large meteoric fireball; a bolide.
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The Collaborative International Dictionary of English v.0.48:

Dragon's blood \Drag"on's blood\, Dragon's head \Drag"on's
head\, Dragon's tail \Drag"on's tail\ .
   See Dragon's blood, Dragon's head, etc., under Dragon.
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