heavy water

noun

1
: the compound D2O composed of deuterium and oxygen

called also deuterium oxide

2
: water enriched in deuterium

Examples of heavy water in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Solar evaporation can take up to two years and requires dry climates, flat land, and heavy water use. Neetika Walter, Interesting Engineering, 21 Jan. 2026 This comes as Washington officials urge residents to prepare for continued heavy waters and possible evacuations. Kimberlee Speakman, PEOPLE, 11 Dec. 2025 The dishwasher can efficiently and effectively clean a wide range of cooking and serving supplies, but items made of wood do not fare well under the high temperature, heavy water pressure, and harsh soaps used by this machine. Taylor Tobin, Southern Living, 26 Nov. 2025 Off Brazil’s northeastern coast, where the sediment-heavy water of the vast Amazon River tips out into the Atlantic, are two very different types of treasure. Laura Paddison, CNN Money, 10 Nov. 2025 See All Example Sentences for heavy water

Word History

First Known Use

1933, in the meaning defined at sense 1

Time Traveler
The first known use of heavy water was in 1933

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Cite this Entry

“Heavy water.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heavy%20water. Accessed 28 Jan. 2026.

Kids Definition

heavy water

noun
: water enriched in deuterium

Medical Definition

heavy water

noun
1
: the compound D2O composed of deuterium and oxygen

called also deuterium oxide

2
: water having a higher-than-usual proportion of deuterium among its hydrogen atoms

More from Merriam-Webster on heavy water

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