| 1. | a mark indicating the height to which water rises or has risen, as in a river or inlet. |
| 2. | water line (def. 5). |
| 3. | a figure or design impressed in some paper during manufacture, visible when the paper is held to the light. |
| 4. | to mark (paper) with a watermark. |
| 5. | to impress (a design, pattern, etc.), as a watermark. |
| 1. | Nautical. the part of the outside of a ship's hull that is just at the water level. |
| 2. | Naval Architecture. any of a series of lines on the hull plans of a vessel representing the level to which the vessel is immersed or the bottom of the keel. Compare load line, Plimsoll line. |
| 3. | the line in which water at its surface borders upon a floating body. |
| 4. | water level (def. 2). |
| 5. | Also called watermark. a line indicating the former level or passage of water: A water line all around the cellar served as a reminder of the flood. |
| 6. | a pipe, hose, tube, or other line for conveying water. |
