A term used to describe the combination of various waves in the ocean in a specific area. The combination of these waves may include ripples, chop, wind waves, and swell, and all from a multitude of different directions. In surf forecasting terms, a "pre-existing sea state" left in an area by a previous storm, can greatly enhance the swell in a following storm passing over the same area within a 48-hour period if the sea state is going in the same direction as the fetch of the new storm.