Loach

from WordNet (r) 3.0 (2006)

loach
    n 1: slender freshwater fishes of Eurasia and Africa resembling
         catfishes

from The Collaborative International Dictionary of English v.0.48

Loach \Loach\ (l[=o]ch), n. [OE. loche, F. loche.] (Zool.)
   Any one of several small, fresh-water, cyprinoid fishes of
   the genera {Cobitis}, {Nemachilus}, and allied genera, having
   six or more barbules around the mouth. They are found in
   Europe and Asia. The common European species ({Nemachilus
   barbatulus}) is used as a food fish.
   [1913 Webster]