Source : Webster's Revised Unabridged Dictionary (1913)

Dhow \Dhow\, n. [Ar. d[=a]o?]
   A coasting vessel of Arabia, East Africa, and the Indian
   Ocean. It has generally but one mast and a lateen sail. [Also
   written {dow}.]

Source : WordNet®

dhow
     n : a lateen-rigged sailing vessel used by Arabs