(n.) A seat or pavilion, generally covered, fastened on the back of an elephant, for the rider or riders.
Example Sentences:
(1) BFG then explains how the phoenix is "fairly obviously a reference to the bombing of the city during World War II and its subsequent rebuilding", and that "the castle on the tusker's back either reflects the walled nature of the city or the howdah (or shed) that used to contain Imperial types and their Mem Sahibs."