A three-masted vessel is a type of sailing ship that has three masts, each with its own set of sails. Two crossword solutions for this term are Xebec (5 letters) and CARAVEL (7 letters). A Xebec is a type of Mediterranean sailing ship that was used by the Spanish, Portuguese, and Barbary pirates in the 16th and 17th centuries. It had a distinctive hull shape and was used for trading and warfare. A CARAVEL is a type of small, highly maneuverable sailing ship that was developed in the 15th century by the Portuguese. It was used for exploration and trade, and was capable of sailing against the wind.