upas

noun
  1. 1

    (usually countable) A tree, Antiaris toxicaria, of the mulberry family, common in the forests of Java and the neighboring islands, with poisonous secretions.

  2. 2

    A virulent poison used in Java and the adjacent islands for poisoning arrows derived from the tree.

  3. 3

    A poison prepared from the climbing plant Strychnos tieute.

Source: https://en.wiktionary.org/wiki/upas