Source : Webster's Revised Unabridged Dictionary (1913)

Howdah \How"dah\, n. [Ar. hawdaj.]
   A seat or pavilion, generally covered, fastened on the back
   of an elephant, for the rider or riders. [Written also
   {houdah}.]

Source : WordNet®

howdah
     n : a (usually canopied) seat for riding on the back of a camel
         or elephant [syn: {houdah}]