slubber

/ˈslʌbər/
noun
  1. A person or machine that twists fibers into a soft, thick strand (slub) during yarn production.
    • The new slubber could process twice as much cotton as the old one.
    • In the mill, the slubber worked quickly to keep the fibers moving.
    • The slubber operated the machine that prepared the wool for spinning.