- To swing off course due to difficult sea conditions or steering troubles.
Probably earlier than the 18th century. Possibly from Icelandic, jaga, meaning to go to and fro. Also possibly from Old Norse, ga, to bend from course.
Very similar to the term used in aviation for sideways aircraft movement. Essentially, the vessel is no longer moving in a straight line according to the direction it’s pointed. Strong winds and currents can cause yawing moments.
Rogers, J.G. (1985). Origins of Sea Terms. Mystic Seaport Museum.