water line

noun

The outline of a horizontal section of a vessel, as when floating in the water.

Meanings

nounwater line (plural water lines)

plural water lines · alternative water-line · alternative waterline

  1. businessThe outline of a horizontal section of a vessel, as when floating in the water.
  2. businessAny one of certain lines of a vessel, model, or plan, parallel with the surface of the water at various heights from the keel. In a half-breadth plan, the water lines are outward curves showing the horizontal form of the ship at their several heights; in a sheer plan, they are projected as straight horizontal lines.
  3. nauticalAny one of several lines marked upon the outside of a vessel, corresponding with the surface of the water when she is afloat on an even keel. The lowest line indicates the vessel's proper submergence when not loaded, and is called the light water line; the highest, called the load water line, indicates her proper submergence when loaded.

    The water line is to that Bend or place she should swim in when she is loaded.

    1627, John Smith, chapter 9, in A Sea Grammar, London: John Haviland, page 45
    2 more examples

    […] Jonah throws himself into his berth, and finds the little state-room ceiling almost resting on his forehead. The air is close, and Jonah gasps. Then, in that contracted hole, sunk, too, beneath the ship’s water-line, Jonah feels the heralding presentiment of that stifling hour, when the whale shall hold him in the smallest of his bowels’ wards.

    1851 November 14, Herman Melville, “Chapter 9”, in Moby-Dick; or, The Whale, 1st American edition, New York, N.Y.: Harper & Brothers; London: Richard Bentley, →OCLC

    None of us were more than shaken by the blast; we pulled ourselves together, and I laid and fired again. And that went better, for I holed her on the water line and that shell burst inside.

    1932, Neville Shute, chapter 15, in Lonely Road, London: Heinemann
  4. The line corresponding to the surface of the water touching any submerged object or body.

    The Lily Lake beaver house, in which the old beaver spent the drouthy winter, was a large roughly rounded affair that measured twenty-two feet in diameter. It rose only four feet above the normal water-line.

    1913, Enos A. Mills, “The Primitive House”, in In Beaver World, Boston: Houghton Mifflin
    1 more example

    Not far away, off our weather bow, there was a little iceberg which had such a queerness about it that the captain and three men went in a boat to look at it. The ice was mighty clear ice, and you could see almost through it, and right inside of it, not more than three feet above the water-line, and about two feet, or maybe twenty inches, inside the ice, was a whopping big shark, about fourteen feet long,—a regular man-eater,—frozen in there hard and fast.

    1897, Frank R. Stockton, “The Widow’s Cruise”, in A Story-teller’s Pack, New York: Scribner, pages 94–95
  5. The level at which water meets land along the shore of a body of water.

    The shore along which they rowed was, at first, wooded to the water line.

    1932, E. C. Brill, chapter 4, in The Secret Cache, New York: Cupples & Leon, page 30
    2 more examples

    Little creeks ran into [the river] in the wet season, but now their dry mouths hung clear above water-line.

    1895, Rudyard Kipling, “The Undertakers”, in The Second Jungle Book, London: Macmillan, page 87

    […] both animals remained upslope, showing no inclination to descend to the water line.

    1960, Andre Norton, chapter 10, in Storm over Warlock, New York: Ace Books, page 106
  6. Used other than figuratively or idiomatically: see water, line.

Synonyms & antonyms

nouna line corresponding to the surface of the water when the vessel is afloat on an even keel; often painted on the hull of a ship

Broader

nouna line marking the level reached by a body of water

Similar
Broader

Synonym sets from Open English WordNet, CC BY 4.0.

Translations

Catalan línia de flotació
  • línia de flotacióline of water along a ship
Czech čára ponoru
  • čára ponoruline of water along a ship
Finnish vesilinja
  • vesilinjaline of water along a ship
French ligne de flottaison
  • ligne de flottaisonline of water along a ship
German Wasserlinie
  • Wasserlinieline of water along a ship
Irish líne shnámha
  • líne shnámhaline of water along a ship
Polish linia wodna, wodnica
  • linia wodnaline of water along a ship
  • wodnicaline of water along a ship
Spanish línea de flotación
  • línea de flotaciónline of water along a ship
Welsh llinell ddŵr, noflin
  • llinell ddŵrline of water along a ship
  • noflinline of water along a ship
Cite this entry
APA

water line. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/water%20line

MLA

“water line.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/water%20line. Accessed November 4, 2026.

Chicago

WatkinsX Dictionary, s.v. “water line,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/water%20line.

Source: water line on Wiktionary, CC BY-SA 4.0.