topsail
A square sail set above the lowest sail on the mast of a square-rigged ship or a triangular or square sail set above the gaff of a lower sail on a fore-and-aft-rigged ship.
A Pirate's Glossary of TermsA Pirate's Glossary of Terms
A square sail set above the lowest sail on the mast of a square-rigged ship or a triangular or square sail set above the gaff of a lower sail on a fore-and-aft-rigged ship.