Meaning

• An instrument with steel pins used to comb out flax or hemp.

• (usually now in the plural) One of the long, narrow feathers on the neck of birds, most noticeable on the rooster.

• A feather used to make a fishing lure or a fishing lure incorporating a feather.

• (usually now in the plural) By extension (because the hackles of a rooster are lifted when it is angry), the hair on the nape of the neck in dogs and other animals; also used figuratively for humans.

  "When the dog got angry, his hackles rose and he growled."

• A plate with rows of pointed needles used to blend or straighten hair.

• A feather plume on some soldier's uniforms, especially the hat or helmet.

• Any flimsy substance unspun, such as raw silk.

Meaning

• To dress (flax or hemp) with a hackle; to prepare fibres of flax or hemp for spinning.

• To separate, as the coarse part of flax or hemp from the fine, by drawing it through the teeth of a hackle or hatchel.

• To tear asunder; to break into pieces.