thermal equilibrium

American  

noun

Thermodynamics.

1. the relationship between two systems connected only by a diathermic wall.

2. the relationship between two isolated systems the states of which are such that no net transfer of energy would occur between them if they were connected by a diathermic wall.

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thermal equilibrium Scientific  

1. The condition under which two substances in physical contact with each other exchange no heat energy. Two substances in thermal equilibrium are said to be at the same temperature.

2. See also thermodynamics

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thermal equilibrium Cultural  

1. In physics and chemistry, a condition in which all parts of a system are at the same temperature.

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Example Sentences

The USC researchers realized that light in these nonlinear environments behaves much like a gas moving toward thermal equilibrium, where random collisions eventually create a stable distribution of energy.

From Science Daily • Oct. 10, 2025

Non-equilibrium phase transition: a change in the state of a system that occurs when it is not in thermal equilibrium, often driven by external forces or energy input.

From Science Daily • Jun. 3, 2024

That’s because the spread of energies available is reduced when there’s thermal equilibrium.

From Salon • Oct. 25, 2023

A key element of an MBL system is its “athermality”: It is not in thermal equilibrium.

From Scientific American • Apr. 20, 2020

The emissivity increases with the temperature, else no state of thermal equilibrium could be reached.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 2 "Ehud" to "Electroscope" by Various