What is the meaning of Hackle?

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

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.

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.

A type of jagged crack extending inwards from the broken surface of a fractured material.

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.

Pluck; courage or energy.

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.

Source: wiktionary.org