hydrazine

noun

hy·​dra·​zine ˈhī-drə-ˌzēn How to pronounce hydrazine (audio)
: a colorless fuming corrosive strongly reducing liquid base N2H4 used especially in fuels for rocket and jet engines
also : an organic base derived from this compound

Examples of hydrazine 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.
As an alternative, the researchers developed an anode that, instead of producing oxygen, breaks down hydrazine, a highly toxic industrial pollutant. — New Atlas, 24 Oct. 2026 The new approach combines hydrazine with a thiophenol derivative, then exposes the mixture to light. — Jijo Malayil, Interesting Engineering, 9 Oct. 2026 The spacecraft was already loaded with nitrogen tetroxide, or NTO, the volatile, toxic oxidizer used by Dragon’s control thrusters in combination with hydrazine fuel. — Stephen Clark, ArsTechnica, 1 Oct. 2026 Technicians loaded the observatory with 290 gallons (1,100 liters) of hydrazine fuel on July 25, then attached it to its payload adapter in early August. — Josh Dinner, Space.com, 24 Aug. 2026 See All Example Sentences for hydrazine

Word History

Etymology

International Scientific Vocabulary

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of hydrazine was in 1887

Rhymes for hydrazine

See All Rhymes for hydrazine

Browse Nearby Words

hydrazidine
hydrazine
hydrazine hydrate
See all Nearby Words

Cite this Entry

“Hydrazine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrazine. Accessed 30 Oct. 2026.

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Kids Definition

hydrazine

noun
hy·​dra·​zine ˈhī-drə-ˌzēn How to pronounce hydrazine (audio)
: a colorless fuming liquid used especially in fuels for rocket engines

Medical Definition

hydrazine

noun
hy·​dra·​zine ˈhī-drə-ˌzēn How to pronounce hydrazine (audio)
: a colorless fuming corrosive strongly reducing liquid base N2H4 used in the production of various materials (as pharmaceuticals and plastics)
also : an organic base derived from this compound

More from Merriam-Webster on hydrazine

Britannica.com: Encyclopedia article about hydrazine

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