The Collaborative International Dictionary of English v.0.48:

Letterwood \Let"ter*wood`\ (-w[oo^]d`), n. (Bot.)
   The beautiful and highly elastic wood of a tree of the genus
   Brosimum (Brosimum Aubletii), found in Guiana; -- so
   called from black spots in it which bear some resemblance to
   hieroglyphics; also called snakewood, and leopardwood. It
   is much used for bows and for walking sticks.
   [1913 Webster]