hydrogen

noun

hy·​dro·​gen ˈhī-drə-jən How to pronounce hydrogen (audio)
-dər-
: 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
often used before another noun
hydrogen gas
hydrogen atoms
a hydrogen vehicle
the hydrogen industry
see Chemical Elements Table compare deuterium, tritium
hydrogenous adjective

Examples of hydrogen in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The plasma turned into a fog of neutral hydrogen and helium gas, but those density waves were frozen into the distribution of matter, a distribution that persists to this day, albeit on much larger scales than back then. Keith Cooper, Space.com, 22 Jan. 2025 Green hydrogen production costs are projected to fall to €5 - 7 per kilogram by 2025, while capacity is set to double, with China expected to hold half by 2027. Sarwant Singh, Forbes, 22 Jan. 2025 Financing for hydrogen exploration and development remains uncertain, and unclear demand forecasts complicate market growth. Kristen Waggoner, Newsweek, 21 Jan. 2025 The fuel was subjected to full reactor heat and hydrogen gas and kept there for 20 minutes – about what a nuclear engine would have to endure during a boost maneuver. David Szondy, New Atlas, 20 Jan. 2025 See all Example Sentences for hydrogen 

Word History

Etymology

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

First Known Use

1788, in the meaning defined above

Time Traveler
The first known use of hydrogen was in 1788

Dictionary Entries Near hydrogen

Cite this Entry

“Hydrogen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrogen. Accessed 30 Jan. 2025.

Kids Definition

hydrogen

noun
hy·​dro·​gen ˈhī-drə-jən How to pronounce hydrogen (audio)
: a chemical element that is the simplest and lightest of all chemical elements and is normally found alone as a colorless odorless highly flammable gas having two atoms per molecule see element
hydrogenous adjective
Etymology

from French hydrogène "hydrogen," from hydr- "water" and -gène "producer"; so called because when hydrogen gas burns, it combines with oxygen to produce water

Medical Definition

hydrogen

noun
hy·​dro·​gen ˈhī-drə-jən How to pronounce hydrogen (audio)
: 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
hydrogenous adjective

More from Merriam-Webster on hydrogen

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