the GNU version of the Collaborative International Dictionary of English
n. A Virulent poison prepared in Java from the gum resin of one species of the upas tree (Antiaris toxicaria).
The Century Dictionary and Cyclopedia
n. The upas-tree of Java.
n. One of the arrow-poisons of Java and the adjacent islands.
Word Usage
"Yet there was comparative freshness in that tent-like apartment, as I entered it that night, shutting the door of mine after me, to prevent ailantus and upas-antiar from following in my wake."