The Collaborative International Dictionary of English v.0.48:

Ousel \Ou"sel\ ([oo^]"z'l), n. [OE. osel, AS. [=o]sle; akin to
   G. amsel, OHG. amsala, and perh. to L. merula blackbird. Cf.
   Merle, Amsel.] (Zool.)
   One of several species of European thrushes, especially the
   blackbird (Merula merula, or Turdus merula), and the
   mountain or ring ousel (Turdus torquatus). [Written also
   ouzel.]
   [1913 Webster]

   Rock ousel (Zool.), the ring ousel.

   Water ousel (Zool.), the European dipper (Cinclus
      aquaticus), and the American dipper (Cinclus
      Mexicanus).
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Water ousel \Wa"ter ou"sel\, Water ouzel \Wa"ter ou"zel\ .
   (Zool.)
   Any one of several species of small insessorial birds of the
   genus Cinclus (or Hydrobates), especially the European
   water ousel (Cinclus aquaticus), and the American water
   ousel (Cinclus Mexicanus). These birds live about the
   water, and are in the habit of walking on the bottom of
   streams beneath the water in search of food.
   [1913 Webster]