# exothermic

> English word · Adjective · frequency rank #69,836

## Definitions
1. That releases energy in the form of heat.
2. That releases heat during its formation, and absorbs it during its decomposition.
3. Of an animal: whose body temperature is regulated by external factors; cold-blooded.

## Etymology
From French exothermique, from exo- (“outside”) + thermique (“of heat”), both ultimately from Ancient Greek. By surface analysis, exo- + -thermic.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/exothermic