Merriam-Webster Collegiate Dictionary - quebracho

 noun  Etymology: American Spanish, alteration of quiebracha, from Spanish quiebra it breaks + hacha ax  Date: circa 1881  1. any of several trees of southern South America with hard wood: as  a. a tree (Aspidosperma ~) of the dogbane family which occurs chiefly in Argentina and Chile and whose dried bark is used as a respiratory sedative in dyspnea and in asthma  b. a chiefly Argentine tree (Schinopsis lorentzii) of the cashew family with dense wood rich in tannins  2.  a. the wood of a ~  b. a tannin-rich extract of the Argentine ~ used in tanning leather