activation energy

noun

: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule

Examples of activation energy in a Sentence

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Additionally, the material exhibits a low activation energy, indicating minimal energy barriers for lithium-ion movement. — IEEE Spectrum, 15 Feb. 2024 This energy is called the activation energy. — Svenja Lohner, Scientific American, 10 Nov. 2016

Word History

First Known Use

1924, in the meaning defined above

Time Traveler
The first known use of activation energy was in 1924

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activation energy
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“Activation energy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/activation%20energy. Accessed 15 Mar. 2025.

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Kids Definition

activation energy

noun
: the least amount of energy required to change a stable molecule into a reactive molecule

Medical Definition

activation energy

noun
ac·​ti·​va·​tion energy ˌak-tə-ˈvā-shən- How to pronounce activation energy (audio)
: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule

called also energy of activation

More from Merriam-Webster on activation energy

Britannica.com: Encyclopedia article about activation energy

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