heavy water

noun

|Updated on: 9 Jun 2018

Definition of heavy water

1 : the compound D₂O composed of deuterium and oxygen — called also deuterium oxide

2 : water enriched in deuterium

Recent Examples of heavy water from the Web

Its rarity made heavy water the Achilles’ heel of the German nuclear bomb program.

— timothy j. jorgensen, Smithsonian, "How a Sneak Attack By Norway’s Skiing Soldiers Deprived the Nazis of the Atomic Bomb," 27 Feb. 2018
Three apartments remain unoccupied and probably will be for some time due to heavy water damage and some fire damage, Lenzi said.

— jim newton, Lake County News-Sun, "Waukegan lightning strike causes apartment complex evacuation during storm," 16 May 2018
Under the deal, Iran permanently altered a heavy water nuclear power plant to prevent it from ever producing plutonium for a bomb.

— oren dorell, USA TODAY, "Iran preps 'industrial-scale' nuke production after U.S. leaves nuclear deal," 11 May 2018
That finding is also shared in the main by U.S. and Israeli intelligence officials, though the Trump administration argues Iran exceeded limits on heavy water production.

— Washington Post, "AP FACT CHECK: Trump vs. truth on the Iran nuclear deal," 10 May 2018
This fluid holds heavy water, whose hydrogen atoms have a neutron along with a proton, as well as two molecules that serve as building blocks for proteins and whose nitrogen atoms hold an extra neutron.

— amina khan, latimes.com, "A search for some of Earth’s most extreme creatures in the West Coast's deepest underwater canyon," 20 Apr. 2018
In October 2016, Iran slightly surpassed a limit on its stockpiles of heavy water, which is used in medical imaging and can also fuel reactors that produce plutonium, a weapons material.

— Bloomberg.com, "Mario Draghi Answers Questions at ECB News Conference," 24 Apr. 2018
The Sacramento region, where lawns are big and summers are hot, traditionally has been one of the heaviest water users in the state.

— dale kasler and ryan sabalow, sacbee, "Why your water provider is fighting California's ban on watering sidewalks | The Sacramento Bee," 15 Mar. 2018
Combined with running faucets, heavy water consumption amid the freeze caused pressure to plummet in the utility's system and prompted a precautionary boil-water advisory for the entire east bank Thursday morning.

— beau evans, NOLA.com, "Seniors struggle in Lower 9th Ward amid boil advisory," 19 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'heavy water.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of heavy water

1933

in the meaning defined at sense 1

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Medical Dictionary

heavy water

noun

medical Definition of heavy water

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

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See words that rhyme with heavy water Britannica.com: Encyclopedia article about heavy water

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heavy water

Definition of heavy water

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