# Maxwell's demon

> English word · Noun

## Definitions
1. A hypothetical creature in a thought experiment. Maxwell’s demon, if it existed, would act as a sort of gate guard by sorting between higher-energy molecules and lower-energy molecules within an enclosed space. Because such a sorting process would tend to decrease entropy, it would violate the second law of thermodynamics.

## Etymology
Named after physicist James Clerk Maxwell (1831–1879) and demon, and probably from Greek daemon, a mythological being intermediate between gods and men.

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