hy·dro·gen | \ˈhī-drə-jən, -dər-\

Definition of hydrogen 

: a nonmetallic element that is the simplest and lightest of the elements, is normally a colorless odorless highly flammable diatomic gas, and is used especially in synthesis — see Chemical Elements Table — compare deuterium, tritium

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Other Words from hydrogen

hydrogenous \hī-ˈdrä-jə-nəs \ adjective

Examples of hydrogen in a Sentence

Recent Examples on the Web

Combined, these reactions allow people to tune the hydrogen production and carbonate formation. Scott K. Johnson, Ars Technica, "Splitting water for fuel while removing CO₂ from the air," 28 June 2018 This breaks down the water into oxygen and hydrogen, which are released separately at the two electrodes. Charles W. Dunnill, Scientific American, "Method of Making Oxygen from Water in Zero Gravity Raises Hope for Long-Distance Space Travel," 10 July 2018 Although there are suggestions for how the 50% cut in carbon emissions can be achieved by 2050, such as batteries and hydrogen fuel cells, none has been tried on big ships yet. The Economist, "A wave of new environmental laws is scaring shipowners," 21 June 2018 Converting hydrogen into ammonia only to convert it back again might seem strange. Robert F. Service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018 Cesium and hydrogen’s subatomic particles behaved in exactly the same way over 14 years, even at different points in Earth’s orbit. Sophia Chen, WIRED, "These Physicists Watched a Clock Tick for 14 Years Straight," 4 June 2018 There is concern lava could trigger the release of deadly hydrogen sulfate gas, reports CBS News' Mark Strassmann. CBS News, "Hawaii volcano lava flows into power plant, sparking fears of deadly gas release," 22 May 2018 The device uses electricity to extract hydrogen from water. Andrew Maykuth, Philly.com, "Bucks firm exports machine that turns water into hydrogen fuel," 28 Mar. 2018 If a hydrogen atom were the size of Earth, the proton at its center would fit inside the Ohio State football stadium. Author: Sarah Kaplan, Anchorage Daily News, "In a cosmic first, scientists detect ‘ghost particles’ from a distant galaxy," 12 July 2018

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

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First Known Use of hydrogen

1788, in the meaning defined above

History and Etymology for hydrogen

French hydrogène, from hydr- + -gène -gen; from the fact that water is generated by its combustion

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Statistics for hydrogen

Last Updated

9 Oct 2018

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Time Traveler for hydrogen

The first known use of hydrogen was in 1788

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More Definitions for hydrogen



English Language Learners Definition of hydrogen

: a chemical element that has no color or smell and that is the simplest, lightest, and most common element


hy·dro·gen | \ˈhī-drə-jən \

Kids Definition of hydrogen

: a colorless, odorless, and tasteless flammable gas that is the lightest of the chemical elements


hy·dro·gen | \ˈhī-drə-jən \

Medical Definition of hydrogen 

: a nonmetallic element that is the simplest and lightest of the elements and that is normally a colorless odorless highly flammable diatomic gas symbol H — see deuterium, tritium Chemical Elements Table

Other Words from hydrogen

hydrogenous \hī-ˈdräj-ə-nəs \ adjective

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More from Merriam-Webster on hydrogen

Spanish Central: Translation of hydrogen

Nglish: Translation of hydrogen for Spanish Speakers

Britannica English: Translation of hydrogen for Arabic Speakers

Britannica.com: Encyclopedia article about hydrogen

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