to change the sail from one side of the boat to the other when changing course with the wind coming from behind the sailboat. When this is done under control it is a routine and safe maneuver. However, due to careless steering or inattention to wind shifts a sailcan accidentally jibe and swing the sail over with such force that the mast may snap off or the vessel be capsized. —Welcome to the SO Glossary Final approval 2-Mar-90