The Collaborative International Dictionary of English v.0.48:

Chough \Chough\, n. [OE. choughe, kowe (and cf. OE. ca), fr. AS.
   ce['o]; cf. also D. kauw, OHG. ch[=a]ha; perh. akin to E.
   caw. [root]22. Cf. Caddow.] (Zool.)
   A bird of the Crow family (Fregilus graculus) of Europe. It
   is of a black color, with a long, slender, curved bill and
   red legs; -- also called chauk, chauk-daw, chocard,
   Cornish chough, red-legged crow. The name is also applied
   to several allied birds, as the Alpine chough.
   [1913 Webster]

   Cornish chough (Her.), a bird represented black, with red
      feet, and beak; -- called also aylet and sea swallow.
      [1913 Webster]

WordNet (r) 3.0 (2006):

chough
    n 1: a European corvine bird of small or medium size with red
         legs and glossy black plumage