hy·​dro·​gen | \ ˈhī-drə-jən How to pronounce hydrogen (audio) , -dər- \

Definition of hydrogen

: a nonmetallic gaseous chemical element with atomic number 1 that is the simplest and lightest of the elements and that is used especially in the processing of fossil fuels and the synthesis of ammonia — see Chemical Elements Table — compare deuterium, tritium

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Other Words from hydrogen

hydrogenous \ hī-​ˈdrä-​jə-​nəs How to pronounce hydrogen (audio) \ adjective

Examples of hydrogen in a Sentence

Recent Examples on the Web Nicola, based in Phoenix, Arizona, designs and builds electric and hydrogen-fueled trucks. John Dorfman, Forbes, 20 Sep. 2021 Similarly, the strange `Oumuamua has been interpreted as a new type of asteroid, such as a frozen chunk of pure hydrogen or nitrogen. Avi Loeb, Scientific American, 19 Sep. 2021 The oil giant pledged to spend $10 billion through 2028 on biofuels, hydrogen production, carbon capture and other technologies, up from a prior commitment of around $3 billion. Francesca Fontana, WSJ, 18 Sep. 2021 While cruising, any energy captured from the sails is stored in a battery bank onboard and can also be used to produce hydrogen. Rachel Cormack, Robb Report, 13 Sep. 2021 With this process, hydrogen replaces fossil fuels both in the manufacture of iron pellets and carbon purification process, Forbes reports. David Kindy, Smithsonian Magazine, 1 Sep. 2021 Meanwhile hydrogen currently is made from methane, and climate-friendlier versions are still in development while also being called out recently in a scientific journal as potentially as bad or worse than fossil fuels. BostonGlobe.com, 21 Aug. 2021 Bond-building products target three types of chemical bonds that naturally exist in hair, including disulfide bonds, hydrogen bonds, and salt bonds. Amber Katz, Better Homes & Gardens, 17 Aug. 2021 The company’s other announcements at Munich were less exciting, but added extra proof of the scale of its commitment to hydrogen. Mike Duff, Car and Driver, 7 Sep. 2021

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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Time Traveler for hydrogen

Time Traveler

The first known use of hydrogen was in 1788

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Statistics for hydrogen

Last Updated

23 Sep 2021

Cite this Entry

“Hydrogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen. Accessed 27 Sep. 2021.

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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 How to pronounce hydrogen (audio) \

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 How to pronounce hydrogen (audio) \

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 How to pronounce hydrogen (audio) \ adjective

More from Merriam-Webster on 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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