endothermic

American  

[en-doh-thur-mik] / ˌɛn doʊˈθɜr mɪk /

Also endothermal

adjective

1. Chemistry. noting or pertaining to a chemical change that is accompanied by an absorption of heat (opposed to exothermic).

2. Zoology. warm-blooded.

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endothermic British  

/ ˌɛndəʊˈθɜːmɪk /

adjective

1. (of a chemical reaction or compound) occurring or formed with the absorption of heat Compare exothermic endoergic

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endothermic Scientific  

/ ĕn′dō-thûr′mĭk /

1. Relating to a chemical reaction that absorbs heat.

2. Compare exothermic

3. Warm-blooded.

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Other Word Forms

• endothermically adverb
• endothermism noun
• endothermy noun

Etymology

Origin of endothermic

< French endothermique (1879); see endo-, -therm, -ic

Compare meaning

How does endothermic compare to similar and commonly confused words? Explore the most common comparisons:

• endothermic vs. exothermic

Explanation

An endothermic reaction is one that absorbs or uses heat energy. Just ask a melting snowman about it. What do green leaves, boiled eggs, and split gas molecules have in common? They have all undergone endothermic reactions, absorbing heat. But just because there’s heat involved doesn’t mean an endothermic reaction is the cause. Its polar — er thermal — opposite, exothermic describes a reaction that makes or gives off heat. It can be easy to confuse the two, but if you can remember that endo means “in” and exo means "out," the heat might not get to you so much.

Example Sentences

On the other hand, being endothermic could have also contributed to megalodon's extinction, since constantly regulating body temperature like this would have expended more energy and thus required more food.

From Salon • Mar. 10, 2025

The bond energy for a diatomic molecule, DX–Y, is defined as the standard enthalpy change for the endothermic reaction:

From Textbooks • Feb. 14, 2019

Melting, vaporization, and sublimation are all endothermic processes, requiring an input of heat to overcome intermolecular attractions.

From Textbooks • Feb. 14, 2019

If the solute’s electrostatic forces are significantly greater than the solvation forces, the dissolution process is significantly endothermic and the compound may not dissolve to an appreciable extent.

From Textbooks • Feb. 14, 2019

"They affect chemical action, retarding it greatly in exothermic actions, speeding greatly endothermic actions," answered X-6221, the greatest of the chemist-investigators.

From The Last Evolution by Morey, Leo