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

Energy is always required to remove electrons from atoms or ions, so ionization processes are endothermic and IE values are always positive.

From Textbooks • Feb. 14, 2019

However, given that modern birds are endothermic, the dinosaurs that served as ancestors to birds likely were endothermic as well.

From Textbooks • Jan. 1, 2015

Some particular endothermic state or form results from the mode of formation and the consequent internal structure of the molecule.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 1 "Evangelical Church Conference" to "Fairbairn, Sir William" by Various