Square-Rigged Ship

Definition

Vessel with primarily square sails set athwartships, the dominant ocean rig until the late nineteenth century.

A square-rigged ship carries its principal sails set athwartships from horizontal yards, the dominant ocean rig from the late medieval period until the late nineteenth century. The arrangement drove large hulls efficiently before the wind but demanded large crews aloft and pointed poorly to windward, which fore-and-aft rigs handled better. The full-rigged ship, the brig, and the bark are square-rigged types; the rig reached its peak in the clippers and the steel windjammers before steam and the motor ship displaced it.