Source : Webster's Revised Unabridged Dictionary (1913)

Crucian carp \Cru"cian carp`\ (-shan k?rp`). [Cf. Sw. karussa,
   G. karausche, F. carousse, -assin, corassin, LL. coracinus,
   Gr. ????? a sort of fish.] (Zo["o]l.)
   A kind of European carp ({Carasius vulgaris}), inferior to
   the common carp; -- called also {German carp}.

   Note: The gibel or Prussian carp is now generally considered
         a variety of the crucian carp, or perhaps a hybrid
         between it and the common carp.