water line

or wa·ter·line

[ waw-ter lahyn, ]

noun

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.
7. waterline, the slightly wet inner rim of skin between the upper or lower eyelashes and the eye, especially with reference to the use of eyeliner:

   Apply pencil eyeliner to your upper and lower waterlines.

water line

noun

1. a line marked at the level around a vessel's hull to which the vessel will be immersed when afloat
2. a line marking the level reached by a body of water

Word History and Origins

Origin of water line¹

First recorded in 1615–25