The Collaborative International Dictionary of English v.0.48:

Bamboo \Bam*boo"\ (b[a^]m*b[=oo]"), n. [Malay bambu, mambu.]
   (Bot.)
   A plant of the family of grasses, and genus Bambusa,
   growing in tropical countries.
   [1913 Webster]

   Note: The most useful species is Bambusa arundinacea, which
         has a woody, hollow, round, straight, jointed stem, and
         grows to the height of forty feet and upward. The
         flowers grow in large panicles, from the joints of the
         stalk, placed three in a parcel, close to their
         receptacles. Old stalks grow to five or six inches in
         diameter, and are so hard and durable as to be used for
         building, and for all sorts of furniture, for water
         pipes, and for poles to support palanquins. The smaller
         stalks are used for walking sticks, flutes, etc.
         [1913 Webster]