Source : Webster's Revised Unabridged Dictionary (1913)

Fishhawk \Fish"hawk`\, n. (Zo["o]l.)
   The osprey ({Pandion halia["e]tus}), found both in Europe and
   America; -- so called because it plunges into the water and
   seizes fishes in its talons. Called also {fishing eagle}, and
   {bald buzzard}.

Source : WordNet®

Pandion haliaetus
     n : large harmless hawk found worldwide that feeds on fish and
         builds a bulky nest often occupied for years [syn: {osprey},
          {fish hawk}, {fish eagle}, {sea eagle}]