exothermic

adjective

exo·​ther·​mic ˌek-sō-ˈthər-mik How to pronounce exothermic (audio)
: characterized by or formed with evolution of heat
exothermically adverb
exothermicity noun

Examples of exothermic in a Sentence

Recent Examples on the Web Climate change has helped to produce most of the planet’s 10 hottest years since the start of the 2010s, creating ideal fire temperatures and ideal fuel on the ground — dry, brittle and ready for exothermic reaction. Dennis Romero, NBC News, 2 Aug. 2022 Be aware that lye is exothermic and will generate a lot of heat (about 200 degrees) when added to the water. New York Times, 13 May 2021 The injection creates an exothermic reaction that ignites the fuels inside the balls. Andre Toran, The Courier-Journal, 31 Mar. 2021 Once started, this exothermic process causes heat (around 500℉), and oxygen is produced. John Cox, USA TODAY, 4 Dec. 2020 In this case, the students hope to combine concepts similar to those found in instant snow and hand warmers to create an exothermic reaction. Elizabeth Depompei, Indianapolis Star, 15 Jan. 2020 To put it in the language of chemistry, Schultz, a chemist, is seeking to catalyze an exothermic reaction. Bradley J. Fikes, sandiegouniontribune.com, 25 June 2018 In modern rockets, such as the Space X Falcon 9 or the Saturn V, the propulsion system is powered by a fast, exothermic reaction between a liquid fuel (usually hydrogen, methane or hydrazine) and oxidizer (usually oxygen or nitrogen tetroxide). Renee Morad, Scientific American, 7 Sep. 2017 For an exothermic reaction, which of the following best describes the effect of increasing the temperature on the forward and reverse reactions? Donna Vickroy, Daily Southtown, 5 Apr. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'exothermic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

International Scientific Vocabulary

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of exothermic was in 1884

Dictionary Entries Near exothermic

Cite this Entry

“Exothermic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exothermic. Accessed 22 Jun. 2024.

Kids Definition

exothermic

adjective
exo·​ther·​mic ˌek-sō-ˈthər-mik How to pronounce exothermic (audio)
: characterized by or formed by the giving off of heat
an exothermic chemical reaction

Medical Definition

exothermic

adjective
exo·​ther·​mic -ˈthər-mik How to pronounce exothermic (audio)
: characterized by or formed with evolution of heat compare endothermic
exothermically adverb
exothermicity noun
plural exothermicities
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