The Collaborative International Dictionary of English v.0.48:

Hackle \Hac"kle\, v. t. [imp. & p. p. Hackled (h[a^]k"k'ld);
   p. pr. & vb. n. Hackling (h[a^]k"kl[i^]ng).]
   1. To separate, as the coarse part of flax or hemp from the
      fine, by drawing it through the teeth of a hackle or
      hatchel.
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   2. To tear asunder; to break in pieces.
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            The other divisions of the kingdom being hackled and
            torn to pieces.                       --Burke.
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