The Collaborative International Dictionary of English v.0.48:

Conger \Con"ger\, n. [L. conger, congrus, akin to Gr. ?: cf. F.
   congre.] (Zool.)
   The conger eel; -- called also congeree.
   [1913 Webster]

   Conger sea (Zool.), the sea eel; a large species of eel
      (Conger vulgaris), which sometimes grows to the length
      of ten feet.
      [1913 Webster]

WordNet (r) 3.0 (2006):

conger
    n 1: large dark-colored scaleless marine eel found in temperate
         and tropical coastal waters; some used for food [syn:
         conger, conger eel]