waterline

noun

wa·​ter·​line ˈwȯ-tər-ˌlīn 

ˈwä-

: a line that marks the level of the surface of water on something: such as

a(1)

: the point on the hull of a ship or boat to which the water rises

(2)

: a line marked on the outside of a ship that corresponds with the water's surface when the ship is afloat on an even keel under specified conditions of loading

b

: shoreline sense 1

Examples of waterline in a Sentence

We repaired the hull below the waterline.

Recent Examples on the Web

White liner was also applied to her waterline, which is a classic makeup trick to accentuate the eyes. — Kara Nesvig, Allure, 27 Sep. 2026

Some of the rocks contain silica, which can form when olivine reacts with water and is particularly abundant in rocks that were once below the lake's waterline. — Samantha Mathewson, Space.com, 24 Sep. 2026

It’s powered by a lithium-ion battery and uses two drive motors and a pair of bulldozer-style treads to navigate the floor, walls, and waterline of your pool. — John R. Delaney, PC Magazine, 10 Sep. 2026

Beginning with a broken waterline and the relief of having an emergency fund, this essay explores single motherhood, career pressure, financial independence and the emotional cost of carrying everything alone. — Kristin Vance Richards, Forbes.com, 18 Aug. 2026

Word History

First Known Use

circa 1625, in the meaning defined above

Phrases Containing waterline

• the waterline

Rhymes for waterline

• alkaline
• andesine
• anodyne
• anticline
• arginine
• asinine
• benzidine
• borderline
• byzantine
• calamine
• caroline
• centerline

Kids Definition

waterline

noun

wa·​ter·​line ˈwȯt-ər-ˌlīn 

ˈwät-

: a line marked on the outside of a ship that matches the surface of the water when the ship floats evenly