open water

noun

plural open waters

: water that is clear of obstacles to passage or view : water that is open (see open entry 1 sense 7a)

The word marsh conjures up a mental picture of a soggy, flat area filled with cattails and other herbaceous vegetation, with ducks sitting on patches of open water.

—Robert H. Mohlenbrock

often, specifically : water that is free of ice

When the river froze in the fall, a mile of open water had been left between two mighty jams.

—Jack London

Polynyas were areas of persistent open water, found throughout the circumpolar arctic, places kept ice-free by currents and wind patterns.

—David R. Masiel

Because the penguins feed in the ocean, they typically set up colonies near open water and must establish new nests when the coastline becomes covered in … ice.

—Science News

Examples of open water in a Sentence

Recent Examples on the Web

The trials mark the first time the aircraft carrier has operated in open waters, moving beyond construction and dockside testing at the shipyard. —Kaif Shaikh, Interesting Engineering, 29 Jan. 2026

Without sea ice, the bears are forced to hunt in open water, and the seals can outswim them. —Julia Jacobo, ABC News, 29 Jan. 2026

Lake-effect snow needs a strong temperature difference (cold air/warm lake), and the lake-effect snow fetch distance is the length of open water wind travels over, requiring at least 60 miles for significant lake-effect snow. —Vytas Reid, CBS News, 28 Jan. 2026

As the Arctic blast moves through, Lake Erie already has extensive ice cover, with 75% of the lake frozen and only a narrow stretch of open water from Conneaut, Ohio, to Dunkirk, New York, according to the National Oceanic and Atmospheric Administration. —Brandi D. Addison, Freep.com, 25 Jan. 2026

Word History

First Known Use

1625, in the meaning defined above

Rhymes for open water

• annunciator
• imprimatur
• underwater
• backwater
• bathwater
• blackwater
• breakwater
• deepwater
• edgewater
• feedwater
• floodwater
• freshwater