[1] : The Collaborative International Dictionary of English v.0.48

wiver \wiv"er\, wivern \wiv"ern\, n. oe. wivere a serpent, of.
   wivre, guivre, f. givre, guivre, wiver, from l. vipera;
   probably influenced by ohg. wipera, from the latin. see
   viper, and cf. weever.
   1913 webster
   1. her. a fabulous two-legged, winged creature, like a
      cockatrice, but having the head of a dragon, and without
      spurs. written also wyvern.
      1913 webster

            the jargon of heraldry, its griffins, its mold
            warps, its wiverns, and its dragons.  --sir w.
                                                  scott.
      1913 webster

   2. zool. the weever.
      1913 webster
see also:
viper weever wyvern 

[2] : WordNet (r) 2.0

wivern
     n : a fire-breathing dragon used in medieval heraldry; had the
         head of a dragon and the tail of a snake and a body with
         wings and two legs syn: wyvern
see also:
wyvern 

Wivern >> W Words
Wivern, definition of term: Wivern
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