harl

/hɑrl/
noun
  1. A fiber or filament, especially one from the outer layer of a feather or from flax or hemp.
    • In textile work, the harl of flax is separated from the woody core.
    • The artist used the fine harl of the feather to create delicate brush strokes.
    • The fly fisherman carefully tied a harl from a peacock feather onto his hook.