Source : Webster's Revised Unabridged Dictionary (1913)

Tucum \Tu"cum\, n. [So called by the Indians of Brazil.]
   A fine, strong fiber obtained from the young leaves of a
   Brazilian palm ({Astrocaryum vulgare}), used for cordage,
   bowstrings, etc.; also, the plant yielding this fiber. Called
   also {tecum}, and {tecum fiber}.