hydrogen

noun

hy·​dro·​gen ˈhī-drə-jən 

-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

hī-ˈdrä-jə-nəs 

adjective

Examples of hydrogen in a Sentence

Recent Examples on the Web

This year, Italian shipbuilder Sanlorenzo will test the first 50-meter steel yacht powered by hydrogen fuel cells, and another 114-meter yacht from German shipmaker Lürssen with the same technology is in production for 2025 for Apple Inc.’s former watch developer Marc Newson. —Eva Roytburg, Fortune Europe, 9 June 2024

The Japanese automaker recently showed off a concept for a hydrogen fuel cell truck and, last year, began testing a stationary fuel cell power station in California. —William Gavin, Quartz, 5 June 2024

Demand for wind could also rise as a growing number of states, tech companies and hydrogen producers are trying to secure clean electricity around the clock, rather than just a burst of solar power in the daytime. —Brad Plumer, New York Times, 3 June 2024

Liquid hydrogen and oxygen make precious rocket propellant, and helium-3 is a rare substance used to improve quantum computers. —Martin Elvis, The Conversation, 30 May 2024

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

Phrases Containing hydrogen

• heavy hydrogen
• hydrogen bomb
• hydrogen bond
• hydrogen bromide
• hydrogen chloride
• hydrogen cyanide
• hydrogen fluoride
• hydrogen iodide
• hydrogen ion
• hydrogen peroxide
• hydrogen sulfide

Kids Definition

hydrogen

noun

hy·​dro·​gen ˈhī-drə-jən 

: 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

hī-ˈdräj-ə-nəs 

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 

: 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

hī-ˈdräj-ə-nəs 

adjective