exo·​ther·​mic | \ ˌek-sō-ˈthər-mik How to pronounce exothermic (audio) \

Definition of exothermic

: characterized by or formed with evolution of heat

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Other Words from exothermic

exothermically \ ˌek-​sō-​ˈthər-​mi-​k(ə-​)lē How to pronounce exothermically (audio) \ adverb
exothermicity \ ˌek-​sō-​ˌthər-​ˈmi-​sə-​tē How to pronounce exothermicity (audio) \ noun

Examples of exothermic in a Sentence

Recent Examples on the Web 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, "Instant snow, hand warmers and a national prize: Center Grove students have a big idea," 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, "Scripps Research, AbbVie join in large cancer therapy alliance," 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, "Build the Best Alka-Rocket Ever—with Science," 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, "Tinley Park High School student is a champion for chemistry," 5 Apr. 2018 Soon, however, the ACA will erupt into an exothermic death trap like ammonium nitrate combined with fuel oil. Katy Waldman, Slate Magazine, "Obamacare Is Imploding! Obamacare Is Exploding!," 27 Mar. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'exothermic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of exothermic

1884, in the meaning defined above

History and Etymology for exothermic

International Scientific Vocabulary

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Time Traveler for exothermic

Time Traveler

The first known use of exothermic was in 1884

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Statistics for exothermic

Cite this Entry

“Exothermic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exothermic. Accessed 12 Aug. 2020.

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More Definitions for exothermic


exo·​ther·​mic | \ -ˈthər-mik How to pronounce exothermic (audio) \

Medical Definition of exothermic

: characterized by or formed with evolution of heat — compare endothermic

Other Words from exothermic

exothermically \ -​mi-​k(ə-​)lē How to pronounce exothermically (audio) \ adverb
exothermicity \ -​ˌthər-​ˈmis-​ət-​ē How to pronounce exothermicity (audio) \ noun, plural exothermicities

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