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A polacca is a type of seventeenth-century sailing vessel, similar to the xebec. The name is the feminine of "Polish" in Italian Language. The polacca was frequently seen in the Mediterranean. It has three single-pole masts, often with a lateen hoisted on the foremast (which is slanted forward to accommodate the large lateen yard) and a gaff or lateen on the mizzen mast. The mainmast is square rigged, after the European style. Special Polaccas were used by Murat Reis, those ships had Lateen sails in front and Fore-and-aft rig behind.

Some polacca pictures show what appears to be a ship-rigged vessel (sometimes with a lateen on the mizzen) with a galley-like hull and single-pole masts. Thus, the term "polacca" seems to refer primarily to the masting and possibly the hull type as opposed to the type of rig used for the sails.

de:Polacker fr:polacre ja:ポラッカ