Source : Webster's Revised Unabridged Dictionary (1913)

Anaconda \An`a*con"da\, n. [Of Ceylonese origin?] (Zo["o]l.)
   A large South American snake of the Boa family ({Eunectes
   murinus}), which lives near rivers, and preys on birds and
   small mammals. The name is also applied to a similar large
   serpent ({Python tigris}) of Ceylon.

Source : WordNet®

Eunectes murinus
     n : large arboreal boa of tropical South America [syn: {anaconda}]