Source : Webster's Revised Unabridged Dictionary (1913)

Jambool \Jam"bool\, Jambul \Jam"bul\, n. [Hind. jamb[=u],
   jamb[=u]l, prop., the rose-apple tree or its fruit, fr. Skr.
   jambu, jamb[=u].]
   The Java plum; also, a drug obtained from its bark and seeds,
   used as a remedy for diabetes.