hydrogen

noun
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

The gaseous hydrogen that will power the trains will be pumped in from a 40-foot-high steel container near the tracks at Bremervörde station. David Grossman, Popular Mechanics, "First Hydrogen-Powered Trains Rolling in Germany," 19 Sep. 2018 Both of the Class 8 trucks use technology from the Toyota Mirai hydrogen fuel cell car and emit only water vapor as emissions. Gary Gastelu, Fox News, "Toyota unveils second-generation hydrogen-powered semi truck," 31 July 2018 Most major rockets rely on engines that run on cold liquid propellants, like cryogenic oxygen and hydrogen. Loren Grush, The Verge, "Europe will fire its record-setting big solid rocket motor this week," 11 July 2018 The hydrogen is taken from water by passing electricity through it, often sourced from solar or wind generators. Jordan Blum, Houston Chronicle, "Exxon Mobil, Chevron help form new methane emissions consortium," 25 June 2018 In producing charcoal, all of the water and much of the hydrogen attached to the organic compounds are removed, leaving carbon. Chris Lee, Ars Technica, "Lumber’s lure: Thanks to physics, viable biofuel may grow in the woods," 5 Apr. 2018 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

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

20 Nov 2018

Look-up Popularity

Time Traveler for hydrogen

The first known use of hydrogen was in 1788

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More Definitions for hydrogen

hydrogen

noun

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

hydrogen

noun
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

hydrogen

noun
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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