Source : Webster's Revised Unabridged Dictionary (1913)

Ravenala \Rav`e*na"la\, n. [Malagasy.] (Bot.)
   A genus of plants related to the banana.

   Note: {Ravenala Madagascariensis}, the principal species, is
         an unbranched tree with immense oarlike leaves growing
         alternately from two sides of the stem. The sheathing
         bases of the leafstalks collect and retain rain water,
         which flows freely when they are pierced with a knife,
         whence the plant is called {traveller's tree}.

Source : WordNet®

traveller's tree
     n : giant treelike plant having edible nuts and leafstalks that
         yield a refreshing drink of clear watery sap; reputedly
         an emergency source of water for travelers [syn: {traveler's
         tree}, {ravenala}, {Ravenala madagascariensis}]