heat death

American  

noun

Thermodynamics.

1. entropy3

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heat death British  

noun

1. thermodynamics the condition of any closed system when its total entropy is a maximum and it has no available energy. If the universe is a closed system, it should eventually reach this state

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heat death Scientific  

1. The eventual dispersion of all of the energy within a physical system to a completely uniform distribution of heat energy, that is, to maximum entropy. Heat death for all macroscopic physical systems, including the universe, is predicted by the Second Law of Thermodynamics.

2. See more at entropy thermodynamics

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Etymology

Origin of heat death

First recorded in 1925–30

Example Sentences

Will it end in heat death, expanding into a frozen and lifeless expanse?

From The Wall Street Journal • May 19, 2026

The calculations used in the paper are based on the most widely accepted hypothesis for the end of the universe, which is the heat death theory.

From BBC • Oct. 31, 2024

No other major metropolitan area in the United States has reported such high heat death figures or spends so much time tracking and studying them.

From Washington Times • Sep. 29, 2023

"The closer wet bulb temperature gets to our body temperature, the less heat is lost and the closer we are to heat death," Reiners, a geosciences professor, writes.

From Salon • Jul. 26, 2022

The universe grows cold and dies a heat death.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife