Oakum /(ōk"ŭm)/

Oak·um

Oakum

n.
  1. The material obtained by untwisting and picking into loose fiber old hemp ropes; -- used for calking the seams of ships, stopping leaks, etc.
  2. The coarse portion separated from flax or hemp in nackling.

Phrases & Compounds
White oakum
that made from untarred rope.