heavy water


Definition of heavy water 

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

Having a fast, non-invasive method such as heavy water tracing would be a great economic boon. Kevin Davenport, idahostatesman, "Yellowstone's magma chamber is more powerful than we knew. Here's why studying it matters.," 3 July 2018 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

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.

See More

First Known Use of heavy water

1933, in the meaning defined at sense 1

Keep scrolling for more

Learn More about heavy water

Share heavy water

Statistics for heavy water

Look-up Popularity

Time Traveler for heavy water

The first known use of heavy water was in 1933

See more words from the same year

Keep scrolling for more

More Definitions for heavy water

heavy water


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

More from Merriam-Webster on heavy water

See words that rhyme with heavy water

Britannica.com: Encyclopedia article about heavy water

Comments on heavy water

What made you want to look up heavy water? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

Dictionary Devil

Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!