equilibrium

American  

[ee-kwuh-lib-ree-uhm, ek-wuh-] / ˌi kwəˈlɪb ri əm, ˌɛk wə- /

noun

equilibriums, plural equilibria plural

1. a state of rest or balance due to the equal action of opposing forces.

   Synonyms:

   stability, steadiness, equipoise

2. equal balance between any powers, influences, etc.; equality of effect.

3. mental or emotional balance; equanimity.

   The pressures of the situation caused her to lose her equilibrium.

4. Chemistry. the condition existing when a chemical reaction and its reverse reaction proceed at equal rates.

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equilibrium British  

/ ˌiːkwɪˈlɪbrɪəm /

noun

1. a stable condition in which forces cancel one another

2. a state or feeling of mental balance; composure

3. any unchanging condition or state of a body, system, etc, resulting from the balance or cancelling out of the influences or processes to which it is subjected See thermodynamic equilibrium

4. physics a state of rest or uniform motion in which there is no resultant force on a body

5. chem the condition existing when a chemical reaction and its reverse reaction take place at equal rates

6. physics the condition of a system that has its total energy distributed among its component parts in the statistically most probable manner

7. physiol a state of bodily balance, maintained primarily by special receptors in the inner ear

8. the economic condition in which there is neither excess demand nor excess supply in a market

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equilibrium Scientific  

/ ē′kwə-lĭb′rē-əm /

equilibriums plural

1. Physics The state of a body or physical system that is at rest or in constant and unchanging motion. A system that is in equilibrium shows no tendency to alter over time.

2. Physics ◆ If a system is in static equilibrium, there are no net forces and no net torque in the system.

3. Physics ◆ If a system is in stable equilibrium, small disturbances to the system cause only a temporary change before it returns to its original state.

4. Chemistry The state of a reversible chemical reaction in which its forward and reverse reactions occur at equal rates so that the concentration of the reactants and products remains the same.

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equilibrium ¹ Cultural  

1. A condition in which all influences acting cancel each other, so that a static or balanced situation results. In physics, equilibrium results from the cancellation of forces acting on an object. In chemistry, it occurs when chemical reactions are proceeding in such a way that the amount of each substance in a system remains the same. (See chemical equilibrium.)

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equilibrium ² Cultural  

1. In economics, a state of the economy in which for every commodity or service (including labor), total supply and demand are exactly equal. Equilibrium is never actually attained; it is approximated by movements of the market.

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Discover More

Keynesian economics departed from conventional economic theory in demonstrating that economic equilibrium and full employment need not occur together. Therefore, as a system tends toward equilibrium, it might not eliminate unemployment.

Other Word Forms

Derived Forms

• nonequilibrium
  noun
• equilibratory
  adjective

Inflected Forms

Nouns

• equilibria
  plural
• equilibriums
  plural

Etymology

Origin of equilibrium

First recorded in 1600–10; from Latin aequilībrium, from aequi- equi- + lībr(a) “balance” + -ium -ium

Explanation

Equilibrium is a state of balance. If you play sports so much that you don't have time for your studies, you need to study more and play less, until sports and studying reach a point of equilibrium. Or become a professional athlete. The word equilibrium is commonly used to refer to mental or emotional balance, and a near synonym in this sense is composure. In chemistry, equilibrium is the condition existing when a chemical reaction and its reverse reaction occur at equal rates. This noun is from Latin aequilībrium, from the prefix aequi-, "equal" plus lībra, "a balance, scale."

Example Sentences

See Examples For:

equilibrium equilibria equilibriums

"Suddenly when they're out of the ground, they're out of equilibrium, and that normally means they start to decay, fall apart."

From BBC ● Jul. 11, 2026

He swears by the practice, saying it’s kept his bowel movements regular and his emotional state at an equilibrium.

From Los Angeles Times ● Jul. 8, 2026

The analysis further argues that comparisons with trophic cascades around the world relied on equilibrium assumptions that do not fit Yellowstone's still recovering, non equilibrium ecosystem.

From Science Daily ● Jun. 14, 2026

“It is a very fragile situation. This equilibrium is not stable because of the risk of miscalculation and unwanted escalation,” said Hamidreza Azizi, a visiting fellow at the German Institute for International and Security Affairs.

From The Wall Street Journal ● Jun. 10, 2026

To stay alive, you have to be able to hold out against equilibrium, maintain imbalance, bank against entropy, and you can only transact this business with membranes in our kind of world.

From "The Lives of a Cell" by Lewis Thomas

Multiple equilibria are possible in a game like this.

From The Wall Street Journal ● Jan. 16, 2026

Such properties include a wide variety of measurable traits such as phase equilibria, density, or heat capacity, for example, that characterize physical systems and determine how chemical processes work.

From Science Daily ● Mar. 13, 2024

"For fundamental research into the dynamics of nutrients and other equilibria in tidal areas, it is very important to understand the role of temperature, salinity, benthic animals and also turmoil by storms."

From Science Daily ● Feb. 22, 2024

The net reaction for these coupled equilibria is obtained by summing the two equilibrium equations and canceling any redundancies:

From Textbooks ● Feb. 14, 2019

By the preservation in successive generations of those whose moving equilibria are less at variance with the requirements, there is produced a changed equilibrium completely in harmony with the requirements.

From Beacon Lights of History, Volume 14 The New Era; A Supplementary Volume, by Recent Writers, as Set Forth in the Preface and Table of Contents by Lord, John

Recent efforts in de-extinction have focused on the Tasmanian tiger, as its natural habitat in Tasmania is still mostly preserved, and its reintroduction could help recovering past ecosystem equilibriums lost after its final disappearance.

From Science Daily ● Sep. 19, 2023

With its limit-pushing positional extremes, McGregor’s ballet vocabulary is often likened to that of William Forsythe — undoubtedly an influence, particularly in the hand grips and precarious equilibriums of the partnering work.

From New York Times ● Jun. 11, 2023

Engineers and architects strive to achieve extremely stable equilibriums for buildings and other systems that must withstand wind, earthquakes, and other forces that displace them from equilibrium.

From Textbooks ● Aug. 12, 2015

Nash equilibriums, which he described in the hieroglyphics of mathematical symbols, exist everywhere.

From Washington Post ● May 24, 2015

By means of this just distribution the different positions, the different paces, and the equilibriums that belong to them, are obtained without effort on the part of man or horse.

From New Method of Horsemanship Including the Breaking and Training of Horses, with Instructions for Obtaining a Good Seat. by Baucher, F.

Related Words

• calmness
• composure
• serenity
• stability
• symmetry