The description of a ship which has movement through the water. The term is sometimes written as under weigh. Theoretically, a ship is considered to be under weigh only when its anchor has been broken out of the bottom while the ship itself is still stationary; it is under way as soon as it begins to move under its own power. However, the two terms have become virtually synonymous, under weigh being a modern spelling distortion of an older term. As a ship's rudder is only effective when the ship is moving through the water, the importance of being under way is that the ship will then answer to its helm and so becomes subject to the International Regulations for Preventing Collisions at Sea.
Subjects: Maritime History.