The Collaborative International Dictionary
Piscivorous
Piscivorous \Pis*civ"o*rous\, a. [L. piscis a fish + vorare to devour: cf. F. piscivore.] (Zo["o]l.) Feeding or subsisting on fish.
Douglas Harper's Etymology Dictionary
piscivorous
1660s, from Latin piscis "fish" (see fish (n.)) + -vorous.
Wiktionary
piscivorous
a. (context chiefly of birds English) That feeds on fish; fish-eating
WordNet
piscivorous
adj. feeding on fishes