The Collaborative International Dictionary of English v.0.48:

Barramundi \Bar`ra*mun"di\, n. [Written also barramunda.]
   [Native name.] (Zool.)
   (a) A remarkable Australian fresh-water ganoid fish of the
       genus Ceratodus.
   (b) An Australian river fish (Osteoglossum Leichhardtii).
       [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

barramundi
    n 1: a species of large perch noted for its sporting and eating
         qualities; lives in marine, estuary, and freshwater
         habitats [syn: barramundi, giant perch, giant
         seaperch, Asian seabass, white seabass, Lates
         calcarifer]