Source : Webster's Revised Unabridged Dictionary (1913)

Roughleg \Rough"leg`\, n. (Zo["o]l.)
   Any one of several species of large hawks of the genus
   {Archibuteo}, having the legs feathered to the toes. Called
   also {rough-legged hawk}, and {rough-legged buzzard}.

   Note: The best known species is {Archibuteo lagopus} of
         Northern Europe, with its darker American variety
         ({Sancti-johannis}). The latter is often nearly or
         quite black. The ferruginous roughleg ({Archibuteo
         ferrugineus}) inhabits Western North America.

Rough-legged \Rough"-legged`\, a. (Zo["o]l.)
   Having the legs covered with feathers; -- said of a bird.

   {rough-legged hawk}. (Zo["o]l.) See {Roughleg}.

Source : WordNet®

rough-legged hawk
     n : large hawk of the northern hemisphere that feeds chiefly on
         small rodents and is beneficial to farmers [syn: {roughleg},
          {Buteo lagopus}]