Dead water
The eddy-water which the ship draws after her at her seat, or line of floatation in the water, particularly close aft. To this particular great attention should be paid in the construction of a vessel, especially in those with square tucks, for such being carried too low in the water, will be attended with great eddies or much dead-water. Vessels with a round buttock have but little or no deadwater, because, by the rounding or arching of such vessels abaft, the water more easily recovers its state of rest.