The Collaborative International Dictionary of English v.0.48:

Throstle \Thros"tle\, n. [OE. throsel, AS. [thorn]rostle,
   [thorn]rosle; akin to MHG. trostel, G. drossel, Icel.
   [thorn]r["o]str, Sw. trast, Lith. strazdas, L. turdus.
   [root]238. Cf. Thrush the bird.]
   1. (Zool.) The song thrush. See under Song.
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   2. A machine for spinning wool, cotton, etc., from the rove,
      consisting of a set of drawing rollers with bobbins and
      flyers, and differing from the mule in having the twisting
      apparatus stationary and the processes continuous; -- so
      called because it makes a singing noise.
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   Throstle cock, the missel thrush. [Prov. Eng.]
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