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.
Like ordinary water, heavy water pairs two hydrogen atoms with one oxygen atom to make each molecule of moisture. — Joseph Howlett, Scientific American, 24 Apr. 2026 During that event, students will walk around the campus to see how heavy water feels when carrying it for long distances, Merlo said. — Julianna Lozada, Daily News, 23 Apr. 2026 The partners worked on pairing fibers and constructions with wash techniques that do not require heavy water and chemical resources. — Angela Velasquez, Footwear News, 21 Apr. 2026 Among Americans’ many concerns about data centers—from the constant humming sound to high electricity prices—heavy water consumption stands out. — Jacqueline Munis, Fortune, 22 June 2026 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

Rhymes for heavy water

See All Rhymes for heavy water

Browse Nearby Words

heavy spar
heavy water
heavy weapons company
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Cite this Entry

“Heavy water.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heavy%20water. Accessed 7 Jul. 2026.

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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

Britannica.com: Encyclopedia article about heavy water

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