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

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 Chairman Mukesh Ambani said the company would invest $10 billion over three years to build four factories to manufacture solar photovoltaic modules, batteries, fuel cells, and electrolysers, for the production of hydrogen. Oliver Staley, Quartz, 19 Nov. 2021 Lawmakers have dedicated $8 billion to create at least four sites that can demonstrate production and storage of clean hydrogen. Leia Larsen, The Salt Lake Tribune, 15 Nov. 2021 But the production of hydrogen isn’t necessarily as clean. Kevin Hand, WSJ, 10 Nov. 2021 At Tokamak Energy, a goal is to eventually heat isotopes of hydrogen hot enough so that their atoms combine in a reaction that releases enormous amounts of energy. New York Times, 18 Oct. 2021 Adnoc has started test shipments of blue hydrogen, a fuel seen as crucial to the energy transition. Akshat Rathi, Bloomberg.com, 7 Oct. 2021 The lasers vaporized the gold, which generated X-rays that heated a pellet of hydrogen the size of a BB. Rob Nikolewski, San Diego Union-Tribune, 26 Sep. 2021 But Soar’s real differentiator is a powertrain that uses direct combustion of liquid hydrogen as a range extender. J. George Gorant, Robb Report, 23 Sep. 2021 Hare warned against the development of blue hydrogen, based on natural gas, as an alternative to other fossil fuels. Ivana Kottasová, CNN, 15 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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Last Updated

22 Nov 2021

Cite this Entry

“Hydrogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen. Accessed 28 Nov. 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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