What does "rook" mean?

Rook: (Zoöl.) A European bird (Corvus frugilegus) resembling the crow, but smaller. It is black, with purple and violet reflections. The base of the beak and the region around it are covered with a rough, scabrous skin, which in old birds is whitish. It is gregarious in its habits. The name is also applied to related Asiatic species. The rook . . . should be treated as the farmer's friend. Pennant.

Additional senses

  1. 2.A trickish, rapacious fellow; a cheat; a sharper. Wycherley.
  2. 3.To cheat; to defraud by cheating. "A band of rooking officials." Milton.

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