The Collaborative International Dictionary of English v.0.48:

Weever \Wee"ver\, n. [Probably from F. vive, OF. vivre, a kind
   of fish, L. vipera viper. Cf. Viper.] (Zool.)
   Any one of several species of edible marine fishes belonging
   to the genus Trachinus, of the family Trachinidae. They
   have a broad spinose head, with the eyes looking upward. The
   long dorsal fin is supported by numerous strong, sharp spines
   which cause painful wounds.
   [1913 Webster]
   [1913 Webster]

   Note: The two British species are the great, or greater,
         weever (Trachinus draco), which becomes a foot long
         (called also gowdie, sea cat, stingbull, and
         weaverfish), and the lesser weever (Trachinus
         vipera), about half as large (called also otter
         pike, and stingfish).
         [1913 Webster]