The Collaborative International Dictionary of English v.0.48:

Mocking \Mock"ing\, a.
   Imitating, esp. in derision, or so as to cause derision;
   mimicking; derisive.
   [1913 Webster]

   Mocking thrush (Zool.), any species of the genus
      Harporhynchus, as the brown thrush (Harporhynchus
      rufus).

   Mocking wren (Zool.), any American wren of the genus
      Thryothorus, esp. Thryothorus Ludovicianus.
      [1913 Webster] mockingbird

The Collaborative International Dictionary of English v.0.48:

Brown thrush \Brown" thrush"\ (Zool.)
   A common American singing bird (Harporhynchus rufus),
   allied to the mocking bird; -- also called brown thrasher.
   [1913 Webster]