kilojoule

noun

ki·​lo·​joule ˈki-lə-ˌjül How to pronounce kilojoule (audio)
ˈkē-lə-
: 1000 joules
also : a unit in nutrition equivalent to 0.239 calorie

Examples of kilojoule 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.
Their 28 kilojoule laser system, the team noted, can at least yield more fusion energy than what is contained in the central plasma—an accomplishment that’s on the road toward NIF’s success, but still a distance away. — IEEE Spectrum, 6 Feb. 2024 But shots in the first 3 years of the ignition campaign only yielded about 1 kilojoule (kJ) of energy each, short of the 21 kJ pumped into the capsule by the x-ray pulse and far short of the 1.8 megajoules (MJ) in the original laser pulse. — Daniel Clery, Science | AAAS, 23 Nov. 2020

Word History

Etymology

International Scientific Vocabulary

First Known Use

circa 1889, in the meaning defined above

Time Traveler
The first known use of kilojoule was circa 1889

Rhymes for kilojoule

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kilojoule
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Cite this Entry

“Kilojoule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/kilojoule. Accessed 24 Mar. 2025.

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Kids Definition

kilojoule

noun
kilo·​joule
ˈkil-ə-ˌjül
: 1000 joules

Medical Definition

kilojoule

noun
ki·​lo·​joule ˈkil-ə-ˌjü(ə)l How to pronounce kilojoule (audio)
: 1000 joules
also : a unit equivalent to 0.239 nutritional calories

More from Merriam-Webster on kilojoule

Britannica.com: Encyclopedia article about kilojoule

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