The Collaborative International Dictionary
Tucum
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.
Wiktionary
tucum
n. 1 A fine, strong fibre obtained from the young leaf of a Brazilian palm (''Astrocaryum vulgare''), used for cordage, bowstrings, etc. 2 The plant that yields this fibre.