water line

American  

[waw-ter lahyn] / ˈwɔ tər ˌlaɪn /

Or waterline

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.

3. the line in which water at its surface borders upon a floating body.

4. water level.

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.

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water line British  

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

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Etymology

Origin of water line

First recorded in 1615–25

Example Sentences

The smallest of the four dams, Copco 2, will come down in 2023, and crews will improve roads and bridges, move a municipal water line, and build a new fish hatchery.

From Salon

Buildings in the hardest-hit towns were reduced to rubble, and the tornadoes ruptured electrical, gas and water lines throughout the region.

From Washington Post

It is spewing from a broken city water line.

From New York Times

Remove the bottom of the stems and pull off any leaves that will be under the water line.

From Washington Post

For sewer drain lines and water lines in commercial buildings, which are wider than residential water lines, this process is well-established.

From Seattle Times