[1] : The Collaborative International Dictionary of English v.0.48

oakum \oak"um\ =ok"u^m, n. as. =acumba; pref. =a-
   cf. g. er-, goth. us-, orig. meaning, out + cemban to comb,
   camb comb. see comb.
   1. the material obtained by untwisting and picking into loose
      fiber old hemp ropes; -- used for calking the seams of
      ships, stopping leaks, etc.
      1913 webster

   2. the coarse portion separated from flax or hemp in
      nackling. --knight.
      1913 webster

   white oakum, that made from untarred rope.
      1913 webster
see also:
comb white oakum 

[2] : WordNet (r) 2.0

oakum
     n : loose hemp or jute fiber obtained by unravelling old ropes;
         when impregnated with tar it was used to caulk seams and
         pack joints in wooden ships

Oakum >> O Words
Oakum, definition of term: Oakum
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