round ship

noun2

1. •
   (historical) A superclass of wooden sailing ship type with a length-to-beam ratio of roughly two to one and normally having one mast with a single square-rigged sail, used as a generic term encompassing most European ancient and mediaeval ships up to the Age of Sail except galleys and longships, variously including or excluding cogs and coccas (the length-to-beam ratio of which could rise to over three to one); a ship (type) of this class.

   • The development in the late thirteenth century of the round ship or cog and the great mercantile galley represented an attempt to provide greater cargo space at lower cost for long - distance trade . — 1981
2. •
   (historical) A Mediterranean type of wooden sailing ship of the Late Middle Ages with a length-to-beam ratio of roughly two or three to one and normally having one or two masts with a single lateen or square-rigged sail (each); a ship of this type.

   • The cocca was the Mediterranean equivalent of the German and north European cog, with a longer hull than the classical Mediterranean round ship (see below, right). — 2017