The Collaborative International Dictionary of English v.0.48:

Cubeb \Cu"beb\ (k[=u]"b[e^]b), n. [F. cub[`e]be (cf. It. cubebe,
   Pr., Sp., Pg., & NL. cubeba), fr. Ar. kab[=a]bat.]
   The small, spicy berry of a species of pepper (Piper
   Cubeba; in (Med.), Cubeba officinalis), native in Java and
   Borneo, but now cultivated in various tropical countries. The
   dried unripe fruit is much used in medicine as a stimulant
   and purgative.
   [1913 Webster]